Nearly half of trade union members are opposed to Britain joining the European single currency, according to the latest ICM poll.

Published in the Times newspaper on Monday, the survey found that 37 per cent think the TUC should be neutral on the issue, with 29 per cent calling for the union to campaign in favour of retaining the pound. Only 22 per cent expected a pro-euro stance.

Of the 505 union members questioned, 49 per cent were opposed to UK membership of the euro, compared with 32 per cent in favour. However, the issue was only ranked as the ninth area of concern out of 11 policy areas, with the NHS and education coming top.

The most pro-euro union was the largest, Unison, although only 110 members were surveyed.

General secretary Dave Prentis has already said that, along with TGWU leader Bill Morris, he would oppose any motion at the TUC conference that supported British entry to the currency in principle, regardless of the wording.

"We cannot possibly have domestic decisions about how much we spend on our schools and hospitals dictated by unelected, unaccountable faceless bankers in Frankfurt," he said.

His argument was disputed by Liberal Democrat Treasury spokesman Matthew Taylor.

"In the long run everyone in Britain, trade union members or not, will benefit from the economic stability offered by the euro. With half a million jobs lost in manufacturing due to instability of the pound this should be obvious to most union members," he said.

"Stories of the euro meaning billions of pounds of public spending cuts are simply scare mongering."

However, Morris argued that too many conflicting opinions existed within the TUC for there to be a general motion.

"The mask of unity within the TUC has come to an end. We have cobbled it together year after year pretending that somehow trade unions are different from the rest of the population," he said.

"The truth is that we are a microcosm of society and we have different views."