Tory leader Iain Duncan-Smith issued a stern warning to party rebels yesterday

He called a press conference for 12.20pm and read out a four-minute statement. In it he took a swipe at "self-indulgent" MPs who put their own personal interests before that of the party.

His move was a reaction to the rebellion by eight Conservative MPs who ignored the three-line whip on the vote to allow single-sex couples to adopt children, which was passed last night by the House of Lords.

They included heavyweights Michael Portillo and Kenneth Clarke.

A further 35 Tory MPs did not vote.

When he announced he would make a statement at 11.40am yesterday it was widely believed that Mr Duncan-Smith might be about to resign in the wake of last night's humiliating defeat.

But he stood firm and warned that the Tory party and his leadership of it would not be scuppered by an undermining minority.

His statement was as follows:
"The Conservative Party membership chose me overwhelmingly and as the first democratically elected leader.
"By electing me the party membership recognised the need for change and the need to take the entire party along that road.
"Over the past year I have discharged the mandate I was given to the letter and I have embarked on some necessary and a sometimes painful process of modernistion.
"I have rededicated the Conservatives to the improvement of public services and we have also begun to reconnect the party to the views and attitudes of contemporary Britain.
"I never underestimated the magnitude of that task but it was a road which it was necessary to travel as a party and I have tried to do that with courtesy, decency and honesty respecting those wanting me to move forward faster and those who saw those moves as threatening.
"Over the last few weeks a small group of my parliamentary colleagues have decided consciously to undermine my leadership and, for a few, last night's vote (Monday) was an attempt to challenge my mandate and as leader of this party. We cannot go on in this fashion.
"We have to pull together or we will hang apart.
"If we are to be taken seriously as an opposition, as an alternative government for this country we have to work together.
"I cannot allow the efforts of a dedicated team in Parliament or of hundreds of thousands of hard working volunteers to be sabotaged by self indulgence and indiscipline.
"The Conservative Party wants to be led. It elected me to lead it in the direction that I am now going.
"My message is simple and stark - unite or die."

Mr Duncan-Smith was elected leader of the Tory party after the 2001 General Election when William Hague stepped down.