Democrats in America are trying to repeal a federal law which upholds the traditional definition of marriage.
The 1996 Defense of Marriage Act (DOMA) defines marriage as a legal union between one man and one woman.
But earlier this week Democrats in both the House of Representatives and the Senate introduced controversial Bills aimed at repealing the Act.
The move comes as the British Government prepares to launch a consultation which will consider fundamentally redefining marriage to include same-sex couples.
The Senate Bill has 19 sponsors – all of whom are Democrats. And the Bill in the House of Representatives has more than 100 sponsors.
Shin Inouye, a spokesman for the White House, said: “The President has long said that DOMA is discriminatory and should be repealed by Congress.
“We welcome the introduction of bills that would legislatively repeal DOMA, and look forward to working with lawmakers to achieve that goal.”
The Bills follow the Department of Justice’s announcement last month that it would no longer defend DOMA against legal challenges, a decision which prompted widespread criticism.
While the federal Government has refused to defend DOMA from legal challenges, it will now be defended by Congress following a move by Republicans.
John Boehner, House of Representatives Speaker, said: “The constitutionality of this law should be determined by the courts — not by the President unilaterally.”
“This action by the House will ensure the matter is addressed in a manner consistent with our Constitution.”
The move was warmly welcomed by Peter Sprigg, a Senior Fellow for Policy Studies at the Family Research Council.
He said: “It makes no sense to extend the benefits of marriage to a type of relationship that is incapable of ever creating children.
“That undermines the whole purpose of the institution and it sends a message to society that children don’t need a mother and a father.”
Homosexual marriage has long been a contentious issue in American politics and in some states it has been imposed on the electorate through judicial activism.
But each time the issue has been put to a vote of the American people it has been rejected.
Last month a senior Conservative MP slammed the coalition Government over an official consultation which will consider doing “away with traditional marriage”.
Edward Leigh MP questioned why the Government was trying to ‘mangle’ marriage, warning that it could have devastating consequences for those who adhere to the traditional definition.
Mr Leigh, a former chairman of the Public Accounts Committee, described the move as “mangling the language of marriage so that, for the sake of the tiny number of gay people who prefer marriage to civil partnership, everyone else in society must have the definition of their own marriage altered forever.
“Once we have departed from the universally understood framework of marriage, there is no logical reason why the new alternative institution should be limited to two people. Why not three? Or thirty-three?
“Same-sex couples already have all the rights of marriage in the form of civil partnership. Why must they also have the language of marriage?
“No doubt because it is an important symbol to them. But it is also an important symbol to many other people.
“Must the religious and cultural heritage of the whole nation be overturned to suit the demands of a minority even of the gay community itself?”