Hundreds of conductors at Arriva Trains Northern walked out for 24 hours at 0001 GMT on Saturday, causing disruption to services.

Further 24-hour stoppages will be held next Tuesday, Christmas Eve and New Year's Eve.

The Rail Maritime and Transport (RMT) Union said it expected the action to be solidly supported, causing "chaos" to services.

'Robust service'

But Arriva claimed that 185 conductors - a quarter of the total - have said they will not join the strikes.

The company said 80% of its network will be covered by services on all four days of action.

Managing director Ray Price added: "Clearly we are very disappointed that the union has decided to hit what is undoubtedly one of the most important times in the year for so many people.

"However, due to the excellent support of those employees not engaged in the strike, and my management team's hard work, we will provide a robust service for customers."

New offers

Arriva said it had made four separate pay offers since the dispute started in January, including the latest suggested deal of a 4% basic rise plus the chance to earn an extra 1% through modernisation and a £200 lump sum.

The union has been campaigning to increase the pay of a conductor from what it said was a basic of £15,500, to more than £17,000.

Arriva said its conductors earned an average of £20,000 a year for a 42-hour week.

The dispute is now one of the longest running in the country and Saturday's strike is the 23rd walkout since the industrial action began.