If there were any lingering doubts that the next general election campaign will be fought over Europe then the latest clash between the prime minister and William Hague must have laid them to rest.

The BBC's Robin Oakley: "The leaders are scraping like farmyard dogs"

In an electrifying exchange on the first day of the new Commons session the two leaders laid into one another over the issue which is dominating political debate.

Mr Hague, always at his best at the despatch box, tore into Mr Blair for planning to drive Britain into a United States of Europe.

Mr Blair countered by claiming the Tories were back in the grip of Thatcherism and were determined to take Britain out of the EU altogether. And he got the best of it.

In a jibe which will come back to haunt Mr Hague over the coming months, the prime minister harked back to comments made by Margaret Thatcher when she anointed John Major as her successor and claimed she would be a good back seat driver.

Accusing the Tory leader of delivering an "hysterical rant", he said: "It's no wonder Norman Tebbit said he had never felt happier in the Conservative Party - the Thatcherites have won, they have taken it over.

Back seat driver

"Not the back seat driver any more, she's kicked him out of the front seat and she's now going to be driving that flat-backed lorry when it goes around the country."

He seized on the recent divisions within the Tories over Europe, reeling off a list of the senior party figures implacably opposed to Mr Hague's line who had last week joined him on the "Britain in Europe" campaign.

And with the likes of Michael Heseltine and Kenneth Clarke on his side, this is an attack that will always draw blood.

It will be no good Mr Hague attempting to come on like Dirty Harry and challenging the former ministers to "make my day" because they may just call his bluff and tear the Tory party in two.

The opposition leader got in a few good punches, but Mr Blair's off-the-cuff replies effectively floored him.

What emerged at the end of the rowdy session, however, was the clearest sign yet of the line both parties are going to take at the next election.

Mr Hague - who is convinced he has felt the pulse of the nation - wants that campaign to be dominated by Europe.

Euro super-state

He will argue that a second Labour government would drive Britain irrevocable into a federal European superstate.

Mr Blair - who also believes he has tapped into the mood of the country - will brand the Tories as closet anti-Europeans who really want to take Britain out of the EU.

This is not the rational, adult and informed debate on Europe which both sides claim they want and neither propositions are accurate.