By Mark Davies BBC News Online political reporter

At a plush country house hotel this weekend, Tony Blair will sit down with Bill Clinton to knock around a few ideas about the future for the centre-left.

Chancellor Gordon Brown will be there too, as will cabinet minister Patricia Hewitt and rising young star David Miliband, the thirtysomething bright spark newly promoted to the government.

The Downing Street policy chief Andrew Adonis is expected to be another guest, as is Geoff Mulgan, who heads Mr Blair's performance and innovation unit.

Forget where we came from, and more important where we are going, and the writing is on the wall

David Miliband and Par Nuder

And who is behind the three-day get together? The Policy Network think-tank, chaired by one Peter Mandelson.

The organisation is backed by Philip Gould, the prime minister's pollster, Lord Levy, Mr Blair's envoy to the Middle East and Anthony Giddens, architect of the Blairite Third Way.

In other words, in terms of New Labour credentials, it is picture perfect.

Big issue

The weekend will begin on Friday with the serious business of England's vital World Cup match with Argentina - though it is unclear whether Mr Clinton will take in the big game.

But once the dust has settled on the drama in Japan, guests will get down to pondering the big issue confronting the centre-left - how to fight back against the gains of the right-wing in Europe and the US.

Mr Clinton is a hero for many in New Labour - the man who led the way in taking on an apparently rampant right-wing in the US.

Mr Blair and his followers watched his success closely, offered their assistance and copied his tactics.

But now, after the apparently unelectable George W. Bush got elected as Mr Clinton's successor in the White House amid right-wing gains in Europe, Mr Blair and his allies recognise the need to think again.

Backdrop

Indeed, Mr Bush's success has inspired Tory leader Iain Duncan Smith, often mocked in the UK as just as unelectable as the US President once was.

The implications will be lost on no-one at the meeting at a Buckinghamshire hotel near Mr Blair's country home of Chequers.

Those at the meeting this weekend acknowledge that there is a big challenge for the centre-left.

A recent article in the Policy Network journal by Mr Miliband and Par Nuder, state secretary in the Swedish prime minister's office, offers an illuminating backdrop to some of the issues likely to be examined this weekend.

The article describes the challenge facing the centre-left as "an urgent intellectual and political task....to offer a coherent response to the challenges of global economic and social change".

Opportunity

The two argue for "innovative ideas" on health, education and welfare and a debate on crime which about effectiveness rather than "about who is toughest".

They write: "The late discovery by the French socialists that crime was a big issue, as the presidential election loomed, led them into the dead-end of turning crime into the biggest issue facing France, which in turn played into the hands of the far right."

They go on to call for reforms of the European Union so that the EU is seen as an opportunity rather than a threat.

And they mirror a growing argument within Labour for the party to finally move on from strategies developed in opposition and continuing in government.

"Many of our strategies for election were developed in opposition," they write.

'Writing on the wall'

"We were guerrilla armies committed to change. In government there are new pressures.

"But continued commitment to offering change, not more of the same, is vital."

Miliband and Nuder conclude by arguing that the success of the likes of Clinton and Blair in the 1990s was based on changing policies while keeping core values at heart.

"That is as important in government, if not more important, as it was in trying to get there," they write.

"Forget where we came from, and more important where we are going, and the writing is on the wall."

That could be the a guiding statement for this weekend's marathon brainstorming session in the countryside.

For working out ways for the centre-left to stay the course - and in some cases getting back on track - will be at the very centre of the debate.