By Ollie Stone-Lee BBC News Online political staff

Labour can avoid an acrimonious and bitter debate about Iraq at its annual conference despite the backbench rebellion in the Commons, its party chairman has said.

In an interview with BBC News Online, Mr Clarke also urged union leaders not to indulge in "gesture politics" over private involvement in public services.

And he underlines the UK Government view that "regime change" is not an end in itself in relation to Iraq.

A rally by anti-war protesters is planned for the eve of the Blackpool conference and Charles Clarke pledged there would be a "full and open" debate on the international crisis.

But he is keen to ensure the Iraq situation does not obscure efforts to showcase the government's "investment and reform" in key public services.

I expect a very full debate, an open debate with differences of opinion expressed

Charles Clarke

Mr Clarke also says his concern is that Labour should not be seen in Blackpool as debating Iraq to the exclusion of the domestic agenda.

In the Commons, 56 Labour MPs registered their opposition to the government's stance on Iraq, but the Norwich South MP denies that vote spells disunity when the conference opens on Sunday.

Rebels

"There are different opinions and the party has always had pacifist group within it - I respect their views but don't agree with them," he says.

He says the rebels were not quite the "usual suspects" but none of the names on the list really surprised him very much.

Most people instead had wanted to see the dossier of evidence against Saddam Hussein and the emphasis on acting through the United Nations - and that is what they got from Tony Blair, argues Mr Clarke.

Some US figures have focussed on Iraq regime change

"I expect a very full debate, an open debate with differences of opinion expressed, but I don't expect an acrimonious or bitter debate in any way," he said.

The cabinet minister underlines Tony Blair's internationalist approach to the crisis and, when asked, says there is a difference of emphasis between the UK and some of the more hawkish US figures.

Middle East efforts

"We emphasise the key need to get rid of the weapons of mass destruction and the question of the Iraqi regime is subsidiary to that," says Mr Clarke.

"There are some reportedly within the American administration - I don't believe President Bush actually - but within the American administration, who see regime change as an end it itself, which we wouldn't.

PFI building projects are causing controversy

"Secondly, we want to drive very, very strongly towards restarting the Middle East process."

Concern about American intentions is prevalent among critics of the government's stance.

Mr Clarke says the rhetoric of the US debate is not always helpful.

But he urges people to judge the American government by its actions, citing George Bush's appeal for the UN to take action as an example of the correct way the president has behaved.

He insists the Iraq crisis will not blow the government's public service drive off course.

Nor will it affect the government timetable on deciding whether to hold a euro referendum - the five economic tests for euro entry are due to be assessed by next June.

Euro questions

But surely it is virtually impossible to see a euro referendum happening with the current situation with Iraq?

Mr Clarke replies: "I don't think so particularly. I don't see it's related. They're completely different questions."

Even if the UK was at war?

"Who knows," he says. "I mean obviously any referendum would have to take account of the particular situation, but we don't even know if there's going to be a referendum yet, let alone what the timing's going to be."

Pensions is set to be a major debating point

Iraq certainly is not the only potential flashpoint for the conference week.

The GMB and Unison are leading union calls for a moratorium on new private finance initiatives until their effectiveness in delivering public service buildings and infrastructure is reviewed.

That would be a "totally self-defeating, crazy act", says Mr Clarke.

Echoing cabinet colleagues John Prescott and Gordon Brown, he says such a move would mean stopping projects which will improve people's lives across the country.

Union message

Mr Clarke acknowledges the big unions could defeat the party leadership on the issue - but it would have "no impact on the government whatsoever".

He points to seven constituency Labour Party resolutions backing the government line - producing a "classic producer-consumer division".

He goes on: "My message to the trade unions would be: the party absolutely values the link with the trade unions.

"It's a critical part of what the Labour Party is and has been and I hope will be

"But for the link to be truly effective we've got to debate seriously as a party of government rather than going for gesture politics of what I think can sometimes be a destructive type.

"And I think the call for a moratorium on PFI falls very much into that category."

Relationship repairs

Before the last Labour annual conference, Mr Clarke said he would have failed if people were saying the relationship between the grass roots and the leadership had not changed after a year.

Now he thinks there is a constructive and positive mood among party activists.

He wants to use the conference to project "what I believe is a true image of a party which is open, having open debates about issues, engaged with the people, not apart from the people".

The one relationship Mr Clarke does want to "improve significantly" is that between Labour and the unions.

"There have been good relationships but too many frictions and broo-hah-hah around the relationship," he says.

Pensions focus

Mr Clarke acknowledges blame on both sides and says the way to improve the links are through "frank conversations about the way we work in government".

He cites the concern about final salary pensions schemes as a key example and expects resolutions to be passed on the issue.

"We can really work together with the trade unions and business to try and address the situation," he adds.

The summer has seen reports of a "whispering campaign" against Mr Clarke among government ranks.

He rejects that suggestion and hopes the "silly season" for such stories is over.