US President Barack Obama is due to speak on immigration reforms later today (Tuesday), and is expected to include binational same-sex couples in his plans.

The speech is set to take place at a campaign-style event in Las Vegas, designed to drum up public support.

Same-sex couples currently have no legal equivalent to laws which allow the non-American partner of an opposite-sex American to immigrate to the country permanently.

As such, many binational same-sex couples are separated when their visa runs out or they are otherwise forced to leave the US.

The Washington Post has said that Mr Obama will likely try to change this by “treating same-sex couples in which one partner is an immigrant the same as married heterosexual couples.”

Last week, he surprised activists when he included an unexpected declaration of support for gay equality in his inaugural address.

Republican Senator John McCain, who ran against Mr Obama in the 2008 elections, has said that he may oppose him on the immigration issue, claiming it was not of “paramount importance”.

“We’ll have to gauge how the majority of Congress feels,” said Mr McCain. “But that, to me, is a red flag that, frankly, we will address in time. We need to get broad consensus over on our proposal to start with. And there are a number of very difficult issues we have to resolve.”

Mr McCain was part of a bipartisan group of Senators who on Monday proposed an immigration reform framework which, although progressive, was not as liberal as the reforms expected to be proposed by Mr Obama. They did not include measures aimed at binational same-sex couples.

The bipartisan support for reforms reflects both parties’ desire to court the vote of Hispanic Americans, who have been a powerful force in recent elections. Mr Obama won 71% of the Hispanic vote in the last election, leading Republicans to soften their stance on immigration.

Mr Obama is also expected to make calls to improve border security and offer ways for illegal immigrants to become citizens at the speech.