By Nyta Mann BBC News Online political correspondent

Prime Minister Tony Blair is facing a test of support amongst Labour MPs over his handling of the Iraq crisis.

The House of Commons is to debate the UN Security Council resolution on Iraq next Monday, with the precise wording of the motion to be unveiled on Wednesday.

Labour MPs have already been issued with a three-line whip - a party's strongest exertion of parliamentary discipline - for when they vote on the motion.

But a rebellion by anti-war Labour backbenchers still looks set to take place, however the motion is framed.

Discussions with Blair offered

Government business managers are nervous about the possible scale of the revolt, with some backbenchers being offered private meetings with Mr Blair and Foreign Secretary Jack Straw to discuss their concerns ahead of Monday's debate.

Backbenchers have been offered private chats with Tony Blair

Criticism of the government's position on the Iraq crisis ranges beyond the "usual suspects" and includes MPs and former ministers on the right and left of the party.

Some MPs fear the US will use the UN resolution to justify military action against Saddam Hussein or an invasion of Iraq without recourse to any further international sanction explicitly backing the use of force.

Their concerns have been fanned by the alleged US "smear campaign" against Hans Blix, head of the UN weapons inspection team in Iraq.

When Mr Straw set out the government's position on Iraq to backbenchers at a meeting of the Parliamentary Labour Party on Wednesday, he restated his view that it was not necessary for a second resolution to be brought before the UN.

Move to marginalise rebels

Government sources confirm that they hope to marginalise anti-war MPs by focusing Monday's debate on support for the UN resolution, rather than approval of British involvement in any possible military action.

Ministers hope this move will confine demonstrations of dissent to hardened anti-war rebels.

More than 50 MPs used a technical motion in September to register their opposition to Mr Blair's Iraq policy.

A number of likely rebel MPs told BBC News Online that for Monday's Commons debate, they hope to force an amendment requiring the issue to go back to the UN Security Council before any attack on Iraq.

Just last week International Development Secretary Clare Short signalled continuing cabinet tensions on the subject when she warned that the UN Security Council alone should decide whether to take military action against Iraq.

But Mr Blair and US President George W Bush have repeatedly insisted they cannot rule out the possibility of taking unilateral action.

Meanwhile, Iraq has promised to meet the 8 December deadline for declaring whether it still holds any weapons of mass destruction.

Mohamed El Baradei, head of the International Atomic Energy Agency, said Iraqi officials made the commitment during talks on Monday night with the UN inspection team.

Meeting the deadline is one of the key conditions laid down in the UN resolution.