The government is "actively considering" an emergency recall of Parliament to debate the Iraq crisis, senior ministerial sources have told BBC News.

No final decision to recall MPs has been taken but the timing of a debate would be likely to depend on when the government's much-trailed dossier of evidence against Saddam Hussein is published.

I do not want it on my conscience that we knew the threat and did nothing

Tony Blair

Pressure for a recall grew on Tuesday evening as the Conservatives joined the Liberal Democrats in calling for Parliament to debate how to tackle Iraq next week.

Those calls came after Tony Blair used his speech at the Trades Union Congress to argue it would be "grossly irresponsible" to allow Iraq to get the weapons it wants.

Speaking in Blackpool, Mr Blair tried to face down hostility to possible military action against Iraq by branding Iraqi leader Saddam Hussein an "outlaw".

Recall pressure

That case against Iraq could soon discussed by MPs, with 27 September - a day after the Liberal Democrat conference - mooted as a possible date if there is a recall.

Labour MP Graham Allen is planning an unofficial debate for MPs if there was no formal recall, although he has been told he cannot use the Commons chamber.

Labour Party chairman Charles Clarke told BBC Two's Newsnight: "We have recalled Parliament in the past, the prime minister has indicated that Parliament would definitely meet before any military action was taken.

Tensions were high in Monday's Iraq debate

"The question of what is the most appropriate timing is a matter we constantly look at."

US President George Bush's speech to the United Nations on Thursday and the evidence dossier would both inform parliamentary debate, said Mr Clarke.

The Liberal Democrats and Conservatives want the debate before the party conferences, with Lib Dem leader Charles Kennedy saying "more substance" was needed in the debate.

Tory leader Iain Duncan Smith said: "What we do over Iraq ... is a critical issue and the way we play it is relevant for Parliament."

Mr Blair used his difficult appearance at the TUC conference to underline the need to confront the Iraqi problem.

Stern test

Acknowledging opposition to action, Mr Blair was resolute, saying: "If we do not deal with the threat from this international outlaw and his barbaric regime, it may not erupt and engulf us this month or next, perhaps not even this year or the next.

"But it will at some point. And I do not want it on my conscience that we knew the threat, saw it coming and did nothing."

	:	Trade unions guide
The big unions at TUC 2002

Mr Blair warned that Saddam Hussein was determined to build a nuclear, chemical and biological arsenal.

"To allow him to use the weapons he has or get the weapons he wants would be an act of gross irresponsibility and we should not countenance it," he said.

On Monday, the TUC appealed for any action to be taken only with the UN's authority, although a call for outright opposition to military action was only narrowly defeated.

Church House has been lined up for an unofficial MPs' debate

Mr Blair suggested the UK and the US must be ready to use military action even if the UN fails to properly tackle the issue.

"If the challenge to us is to work with the UN, we will respond to it," he said.

"But if we do so, then the challenge to all in the UN is this: the UN must be the way to resolve the threat from Saddam, not a way of avoiding it."

Talking of the "daunting" international agenda, Mr Blair also outlined the need to put the Middle East peace process back on track and continue the fight against terrorism.

'Unconvinced'

Mr Blair's Iraq message was heard in silence, although without the heckling some had predicted.

Bob Crow, general secretary of the RMT union, said the speech had done "nothing to convince" him or his delegation.

"He seems hell-bent on having a war with Iraq whatever is said," added Mr Crow.

Both TGWU leader Bill Morris and Amicus joint general secretary Derek Simpson, however, said they were heartened that Mr Blair wanted to use the United Nations.

The TUC speech also saw Mr Blair tackle criticism of his domestic policies in his speech and he urged trade unionists to shun "self-indulgent rhetoric".