The government must set a date for a referendum, Roger Lyons, general secretary of Amicus will tell the union's annual conference in Blackpool.

Mr Lyons will also call for unions to have access to every workplace in Britain on the second day of the private sector union's conference.

Speculation and leaks over the euro poll is shaking manufacturing

Roger Lyons Amicus

He will tell delegates on Sunday the "in-out, in-out" speculation over UK entry into the euro is holding back manufacturing.

Ahead of the Sunday's meeting he said: "More than 10,000 jobs are being lost from manufacturing every month as a result of the overvalued pound against the euro.

"The speculation and leaks over the euro poll is shaking manufacturing about."

By announcing a referendum date. Mr Lyons added, the government would bring relief to British industry.

'Razor wire'

The Treasury's five economic tests on euro entry are to be decided upon by June 2003.

In a separate development, the general secretary was also expected to tell the conference that many people are being denied their right to join a union.

He says employers make it difficult for unions to provide information on membership.

The government hopes holidaymakers will become euro supporters

"Anti-union employers are exploiting the legal regulations to deny unions access to their employees.

"We need 10% membership in any workplace to trigger a ballot for union recognition.

"So anti-union employers surround their staff with razor wire and hi-tech surveillance equipment to make it impossible for trade unionists to communicate with them."

On Saturday, a poll of the union's members published at the conference revealed overwhelming support for strike action to save final salary pension schemes.