Image source, PA Media

There is "absolute unanimity" among members of the RMT union that action is needed to fight the proposals put forward, says the RMT's Jared Wood at a picket alongside striking workers.

The union is taking action over plans to introduce a voluntary compressed four-day working week, which it says could lead to fatigue and impact safety.

Wood says the strike is not just about a four-day week, but that there are other issues were involved, such as the length of shifts and changes to annual leave.

"TfL need to come forward with changes to their proposals for this dispute to be resolved," he says, adding that there was now “a lot of bad feeling” between the drivers and London Underground.

“There is absolute unanimity among our members that we have to fight these proposals."

TfL has said the proposed changes "allows us to offer train operators an additional day off" and "would be voluntary".

James W Kelly
Outside King's Cross station

George, another stallholder outside King's Cross station, says today has been a "particularly quiet" Tuesday due to the strikes.

He says his customers are made up of commuters and tourists, so he's worried about the likely impact over the week as strikes continue.

Despite the potential impact on business, his message to striking RMT drivers is to "keep up the fight".

James W Kelly
Outside King's Cross station

One stall worker at the Real Food Market, outside King's Cross station, says despite the lovely weather there's been next to no footfall due to the strikes.

"It's really heavily impacted sales, especially today," says Mimi, on the Borough Cheese Company stall.

"There's been like no people walking through, so no customers," she says, adding that she also struggled to get into work today.

"Usually when it sunny more people are out... more people want to spend their money, all good, but even though the sun's out today no ones here because the Tubes aren't running," she adds

Barry Caffrey
At South Kensington station

Here at South Kensington station I've been speaking to those who've been impacted by the strikes.

Earlier, Elena told me she'd been caught out by them while trying to fly back home.

"I'm trying to get to Victoria station to catch my flight back to Denmark, from Gatwick," she told me.

"I was about to take a walk, but it's going to take like 40 minutes," she added.

"So yeah, I might be missing my flight."

The shutters are coming down on some stations along the Piccadilly line with passengers turned away as the full effects of the strike begin to show.

In its latest update, TfL says the Piccadilly line is shut westbound between Cockfosters and Acton Town, with reduced service further west.

It adds that the eastbound service between those stations two is still running - for now - however our reporter at Covent Garden says there is no service at the station.

The TfL app is reporting a few eastbound trains in service.

Two hours since the RMT Tube strike went into effect, there is disruption across many lines throughout London.

Transport for London (TfL) lists the Circle line as fully suspended and the Piccadilly as part suspended - these are the two lines where no service is expected when the strikes are in place.

Other affected lines are the Metropolitan, which will not run between Baker Street and Aldgate, while the Central line is suspended between White City and Liverpool Street.

However, as TfL previously warned, there is disruption elsewhere on the network, with the Bakerloo, District, Jubilee all reporting severe delays - with the Northern and Victoria lines reporting minor delays.

The Windrush line has minor delays as a result of a signal failure rather than strike action.

Nisha Patel
At Liverpool Street station

Maria Jose has travelled to London from Uruguay for this weekend's London Marathon, and had planned to spend the days leading up to the race sight-seeing.

However, she says the walkout is going to significantly affect her time in the capital.

"It's going to have a huge impact because we need to go around the city," she says.

"It's not good news because you need everything to flow."

Tom Edwards
BBC London transport correspondent, at Covent Garden station

Here at Covent Garden station, the final Piccadilly line trains are departing, and they won't be returning until after this first wave of strike action ends at midday on Wednesday.

The Piccadilly is one of two Tube lines, along with Circle, that will be completely suspended in this 24-hour period, although disruption is expected on most lines.

Gianluca Capilungo, who owns a cafe near Covent Garden station, says the strike will be damaging to his business and has already seen a big drop in customers in just the first hour alone.

Jess Warren
BBC London

Responding to the walkout, TfL says the RMT's industrial action "completely unnecessary" and that drivers can remain on a five-day week if they want to.

Claire Mann, TfL's chief operating officer, says the proposals would allow it to "offer train operators an additional day off, whilst at the same time bringing London Underground in line with the working patterns of other train operating companies, improving reliability and flexibility at no additional cost".

She adds: "The changes would be voluntary, there would be no reduction in contractual hours and those who wish to continue a five-day working week pattern would be able to do so."

Jess Warren
BBC London

Image source, PA Media

As a reminder, the series of six 24-hour walk outs are being held by members of the Rail, Maritime and Transport (RMT) union, which represents roughly half of drivers on the Tube network.

The drivers are striking over a voluntary proposal made by Transport for London (TfL) to allow train operators to move to a compressed four-day week.

The RMT says the change will mean the working day would be too long under the plans, risking driver fatigue and compromising safety.

The union's London transport regional organiser Jared Wood says the negotiations with TfL left his members feeling "there is absolutely no alternative but to proceed with the strike action".

James W Kelly
At Caledonian Road Tube station

The shutters are still open here at Caledonian Road, a Piccadilly line station, 20 minutes after the strike officially kicked off.

It's among the two lines expected to close entirely - the other being Circle - but station staff are telling passengers it could be open for another hour.

Image source, Getty Images

As the Tube strikes have just come into effect, a spokesperson for London's mayor Sadiq Khan has released a statement urging a "swift resolution" to the dispute.

"Strikes are bad for London and bad for Londoners, particularly for all those businesses who rely on commuters coming into our city," the statement reads.

“Most of the Tube and TfL services will continue to run throughout this week, but Londoners should check before they travel.”

The first of six scheduled Tube strikes has just begun, as of 12:00 BST.

Members of the Rail, Maritime and Transport (RMT) union voted to strike in opposition of the introduction of a four-day working week with condensed hours.

This first strike is set to run for 24 hours, ending at 11:59 on Wednesday.

No service is expected on the Piccadilly and Circle lines during the strike, nor on the Metropolitan line between Baker Street and Aldgate. Central line services will not run between White City and Liverpool Street.

However, "significant" disruption is also expected on most Tube lines, says Transport for London (TfL).

James W Kelly
At Arnos Grove Tube station

"That's so stupid, why are they striking?"

That's the reaction of one woman outside Arnos Grove station after learning the industrial action is set to close the Piccadilly line.

The woman, who asked not to be named, says she was unaware of the walk out and isn't sure how she'll get to work at 13:00 BST.

"It's going to cause a lot of disruption," she says, before adding it "makes sense" when she looks up the RMT's reason for the strike.

James W Kelly
At Cockfosters Tube station

I'm at the very end of the northern end of the Piccadilly line and the strike message appears to have gotten through.

Only a handful of passengers are coming and going.

A staff member at Cockfosters station tells me the last train south into London is expected at about 11:40 BST.

After that, commuters in this community will have to turn to other options.

One man who stopped with me for a chat says the closure of the station will "cause a lot of upheaval".

"It seems to be happening more frequently... it's not good," he adds.

Nisha Patel
At Liverpool Street station

Image source, PA Media

At Liverpool Street Station this morning, hire bikes were disappearing from their docking stations rapidly during the morning commute.

The head of policy at e-bike hire company Forest, Alex Berwin, tells me the company is "already seeing a lot more people using the bikes compared to a regular week".

He says the company expects hire rates to increase as the strike action takes hold.

"During the last strikes last year, we saw around 10 times the number of app downloads than we would see on a regular weekday," he explains.

"Our advice is to wear a helmet, plan your route - preferable long some of the cycling routes - and take your time."

Nisha Patel
At Liverpool Street station

Commuters at Liverpool Street - the busiest station in the UK - have been telling me about how the strike will be affecting them

"[It is] good for my step count but not for my ability to be on time," one woman says. "I was not very well planned this time.

"If I hadn't had an email from some colleagues explaining it, then I wouldn't have realised," she adds.

Another man says the strike has left him paying "extortionate parking prices" as he chose to drive instead of using the Tube.

"It definitely has a big effect on everyday life," he says.

Image source, TfL

It's nearly an hour before the walkout begins but more disruption is hitting the Tube network, with the Circle line now completely suspended.

Delays are also happening on Central, District, Jubilee, Metropolitan, Piccadilly and Victoria lines as a result of the strike.

In addition, the Mildmay and Windrush lines are experiencing non-strike related delays.

You can keep up to date using the TfL status checker., external

James Kelly
Outside Caldedonian Road Tube station

At Caldedonian Road Tube station, which is on the Piccadilly line, this visitor to London tells me he was prepared for the strike.

"I was aware of it so I already made plans to head back before they start," he says.

Nevertheless, the industrial action continuing into Wednesday morning has thrown a spanner in his travel plans.

“I need to travel to Stansted Airport so that’s going to be a fun thing,” he adds.

No, only drivers who are members of the RMT are taking part, which is about half of the workforce.

Members of the Associated Society of Locomotive Engineers and Firemen (Aslef) are not striking, meaning some services will still run, although disruption is still expected to be widespread.

Aslef has accepted TfL’s proposal for a voluntary compressed four-day week and questioned the RMT’s decision to strike.