FOREIGN Secretary Jack Straw has revealed that he became convinced of the need for a referendum on the European Constitution because of conversations with constituents in Blackburn.

He relayed these back to Tony Blair and his Cabinet colleagues.

As the Prime Minister confirmed the U-turn on the national vote, Blackburn MP Mr Straw said: "I think it's the right decision.

"Its never easy for anyone to change their minds let alone for a government.

"But I think the public will give us the credit for listening.

"I became convinced that we needed to hold a referendum on this, not least because of a number of conversations and chance encounters in Blackburn including at my open-air meetings.

"But it was also in pubs where I encountered people who were worried about the issue.

"But when I explained the detail, people seemed to be reassured, but they said if it was so simple why weren't we giving them a chance to vote on it.

"And indeed if it wasn't as simple as that they were even more interested in the vote.

"I have heavy responsibilities for government policy in this area."

Mr Straw, who is initially opposed to a referendum, is being widely credited in Whitehall for changing the Prime Minister's mind and influencing the Cabinet towards a vote.

The likely timescale is an agreement on the constitution in June with it being signed around September following it being translated into the appropriate languages for all the 25 member states.

There would be a Bill to ratify the treaty subject to a referendum in the Queen's Speech in November followed by full consideration of that Bill by the House of Commons and the House of Lords.

That would mean a referendum vote in the autumn -- probably late October or early November -- which would mean the referendum took place after any general election expected in the late spring or early summer.

Tory Leader Michael Howard wants the referendum vote before a general election and was today telling the government it must move for an early vote.