The Bill, presented by Labour MP Kevin McNamara, would have enabled MPs like Gerry Adams and Martin McGuinness of Sinn Fein to take their seats in the Commons without having to swear an oath to the queen.

Mr McNamara said an alternative oath was essential to prevent some MPs starting their careers on a note of "deception and possibly hypocrisy".

Change not necessary

The Bill was opposed by the former Conservative Northern Ireland Secretary Peter Brooke, who said: "If and when we come to make the change it should be a considered judgement and not to solve a local difficulty."

Brooke: in favour of retaining the centuries old oath

He argued that the present oath, whose history dates back centuries, did not stop MPs coming into the House and attempting to change the system from within.

But he did say, refering to Mr Adams and Mr McGuinness:

"It is not unreasonable for us to ask those who pride themselves on their Irish history and their Irishness to pay some attention to our own history."

Ballot box better than armalite

But Mr McNamara said that British politicians had for a long time now talked about the "superiority of the ballot box over the armalite, and have demanded that those from the Irish republican tradition renounce the use of violence and seek change exclusively by democratic and peaceful means.

"Is it not then a hypocrisy of the first order to argue that Irish republicans should contest elections to find only when they have succeeded in winning those elections they are denied their right to fulfil their mandate and to represent their electorate?"

An alternative oath

Mr McNamara suggested an alternative oath along the lines of one draw up by the veteran campaigner for constitutional change, Labour MP Tony Benn.

Adams and McGuinness outside the Commons

Under this proposal MPs would be required to say:

"I do solemnly declare and affirm that I will, to the best of my ability, discharge the responsibilities required of me by virtue of my membership of the House of Commons and faithfully represent those who I serve here."

But Mr Brooke told the House the oath was centuries old and had not been deliberately draw up to exclude any members from taking their seats.

"If a man or a woman seeks to sit in this house the oath of allegiance is essentially a password to entrance. Once the password has been uttered it does not stop members seeking to change our constitution."