BBC Chief Political Correspondent John Sergeant: "This is a slap in the face for Mr Blair"

Despite the opposition of 65 of its own backbenchers the government pushed its controversial proposals on welfare reform through the Commons with a majority of 40 votes.

In the end 270 MPs voted against the government's reforms, while 310 backed the changes.

The vote was closer than expected, with up to 40 Labour MPs abstaining or not voting.

Alistair Darling: We believe in the welfare state

The Welfare Reform and Pensions Bill now faces a rough ride in the House of Lords.

After the vote Labour peer Lord Ashley, who is himself disabled, revealed that he would be tabling the "rebel" amendments in the Upper House. "The battle goes on," he said.

Opponents of the measures fear that as many as 170,000 people could be made worse of by the bill.

Defending the reforms in the Commons debate, Social Security Alistair Darling said: "The idea that our reforms are designed to save money is not true."

He told MPs that none of the changes would affect present claimants and said that the government was committed to "tackling poverty and the causes of poverty".

Mr Darling said the reforms would restore incapacity benefit to its original purpose which he said was to replace income people lost through sickness and invalidity, rather than a subsidy for early retirement.

Turning to the �50 threshold for personal pensions income before means-testing applied to the benefit, Mr Darling said he would keep the figure "under review".

Introducing the rebel amendment, Roger Berry MP, the secretary of the parliamentary disablement group, said the effect of the bill would be "to reduce benefits for disabled people who are unable to work".

Over the next 10 years he predicted this would hit 335,000 people.

He told MPs: "As soon as the pension of a disabled person who is unable to work reaches �2,652 a year, they start to lose incapacity benefit.

BBC Political Correspondent Carole Walker: "This is the biggest rebellion the Government has faced so far"

"People who are unable to work, who have made personal provision for their future financial security, would find themselves facing an effective marginal tax rate of 50%, somewhat greater than the current marginal tax rate for the richest income earners in the country and indeed higher than for MPs."

He was joined in opposing the bill by former minister Tom Clarke who said: "It will be the first time I have not supported my own party in all of my time in Parliament - and I say that of the party I love."

For the Liberal Democrats, welfare spokesman David Rendel opposed the proposals saying they amounted to "work for those who can, but cuts for those who cannot".

Frank Field: "Voting with a heavy heart"

The former minister for welfare reform, Frank Field also spoke out against the bill saying it was "an attack on what _ the prime minister tells the country welfare reform is about".

Labour backbencher Audrey Wise said: "It isn't enough to say we are improving it [incapacity benefit] for some people" when she said the cuts would be "making savings at the expense of some of those who are disabled and chronically sick, and I object to that".

Labour MP Tom Levitt spoke for the reforms saying: "This bill does address the real needs of disabled people and it finances it by redirecting some of those funds from some relatively wealthy people to those who have nothing."

Tory social security spokesman Iain Duncan Smith attacked the government's proposals saying means-testing incapacity benefit would only serve to create "greater dependency".