Updated: 15 February 13:08 – Democratic Senator Patrick Leahy proposed a bill that would allow US citizens to sponsor their same-sex partners for residency visas, in a Congress session on Wednesday.

Mr Leahy, Senator for Vermont, had introduced the, Uniting American Families Act, five times before and been unsuccessful each time, but he now has the backing of President Barack Obama.

Although the Defence of Marriage Act is no longer enforced in many areas of the law, one of the areas in which it is still widely enforced is immigration law, meaning binational same-sex couples do not have the same access to settlement in the US as heterosexual couples.

“Among developed countries with cultures of respect for human rights and fairness, the United States policy in this regard is not living up to our great traditions of equal treatment under the law,” Mr Leahy said.

“We can and should do better,” he added. “I hope all senators will agree that the United States should not have a policy that forces Americans to choose between their country and the ones they love.”

Mr Leahy said he was moved by the plight of American citizens who “worry daily when [their spouse] will be required to leave the US, and some who suffer the heartbreak of a long-distance marriage when their spouses are denied even a visitor visa.”

Mr Leahy had previously hoped to include provisions to extend visas for battered victims of domestic violence in the Violence Against Women Act. However, Republican lawmakers opposed the provision on the grounds that it would affect expenditure.

President Obama’s State of the Union address on Tuesday was attended by a couple whose lives would be significantly benefited by the bill.

Kelly Costello and Fabiola Morales were invited as guests of Representative Jerrold Nadler. Although the two women are married and expecting a child, Ms Morales will have to leave the US when her student visa expires under the law as it currently stands

Several states have found that DOMA is unconstitutional, and although it has not been repealed, in February 2011, President Barack Obama said his administration would cease to defend the federal ban on equal marriage.

In January, the US Supreme Court announced that it would hear two days of arguments relating to same-sex marriage at the end of March.