Proposals for a part-elected and part-appointed House of Lords are "wrong and will not work", the prime minister has told MPs

Ahead of a crucial vote on the issue next week, Tony Blair gave his backing to an entirely appointed second chamber.

"Do we want an elected house or do we want an appointed house? I personally think that a hybrid between the two is wrong and will not work," said Blair.

"The key question on election is do we want a revising chamber or a rival chamber. My view is that we want a revising chamber and I also believe that we should never allow the argument to gain sway that this House of Commons is not a democratically elected body as I believe it is."

And he warned against backing an elected second chamber for reasons of political expediency.

"Every member of this House should realise that we are trying to reach a constitutional settlement not just for one parliament," he said.

While he conceded that there were "a range of views" within the government, Blair said there was widespread agreement on the need for reform.

"Everyone agrees that the status quo should not remain," he added. "Everyone agrees that the remaining hereditary peers should go. And everyone agrees, what's more, that prime ministerial patronage should go."

The intervention comes ahead of next week's free vote on the sliding scale of options on the composition of the second chamber.

Opponents of elections to the upper house will hope Blair's intervention has increased the chances of MPs backing that option next Tuesday.

A series of high profile cabinet ministers are opposed to introducing elected members to the Lords - fearing it will lead to increased tension between the two chambers and demands for increased powers for the upper house.

They include the lord chancellor, Lord Irvine of Lairg, and the deputy prime minister, John Prescott.

Robin Cook, the Commons leader, is spearheading the campaign for a significant proportion of elected members.

Whilst the Conservatives and the Liberal Democrats support a majority-elected chamber, opponents of the move believe a significant number of Labour MPs may back the appointed option.

A recent opinion poll, however, found that the majority of MPs support elections for 60 per cent of the seats in the Lords.

Blair's support for the all-appointed option is likely to provoke anger amongst some MPs.

They argue that such a move would be tantamount to breaking a 2001 manifesto pledge - which committed the government to making the second chamber more "democratic".

It will also find little support amongst the public - just three per cent of whom are said to back an appointed upper house.

Blair, who is committed to attending a summit in France next Tuesday, is unlikely to be able to attend the vote in person.