Tony Blair has slammed as "completely misguided" the European parliamentary vote to scrap the UK opt-out from the working time directive.

Labour MEPs were among those in the European parliament who backed the end of the opt-out clause, which allows individuals to work over a maximum 48 hour week if both employees and employers agree.

The UK has made it clear that it is strongly in favour of retaining the clause, and is supported by Conservative and Liberal Democrat MEPs.

Speaking to journalists at his press conference on Thursday, the prime minister said: "I think the vote is wrong. It is completely misguided."

Blair confirmed he had "no intention whatever" of abolishing Britain's opt-out, and said he believed the government would be able to reverse the vote through the council of ministers.

"We actually believe we have a blocking minority," Blair said.

"What happens if we fail? We'll have to see at that stage."

Referendum

When asked to give a date for the European Union constitution referendum, Blair declined saying only that it would be "done in a stable and orderly way".

The Constitution did not embed either the French or Anglo-Saxon social models, he said.

"What we have got to be doing is changing not the principles behind the social model but changing fundamentally the way those principles are applied," added Blair.

"I don't know that the constitution really answers that question, frankly, either way."

Euro

On the issue of Britain joining the euro, the prime minister said it was only his ambition to sign up if the economic conditions were right.

He said the political case for being involved in any part of the European project was overwhelming.

But he stressed that the euro was different because Britain could only join if the economic conditions were right.

"You can't do it unless the economic conditions are in the right place, and they are not at the moment," Blair said.

"As I said in the course of the election campaign at the moment it is difficult to see in the near future how they are going to come into place.

"But we keep the option open, there is never any point in closing it off and things can change."