US President Barack Obama will mention the country’s ban on gays serving openly in the military in his State of the Union address tomorrow, a senior lawmaker said.

Under a 1993 law, gays and lesbians can serve in the US military if they keep their sexual orientation secret. Obama criticised the law in his 2008 election campaign and promised to repeal it.

He will make his State of the Union address on Wednesday evening. The address serves to outline the president’s legislative agenda and priorities, as well as reflecting on the state of the nation.

According to Reuters, Senator Carl Levin, chairman of the Senate Armed Services Committee, told reporters that Obama would make reference to the gay ban in his address.

Levin, who is in favour of repeal, said: “We were told by the Pentagon that they expected the president to say something in the State of the Union on it.”

But he added he had “no idea” what Obama will say.

Levin added that he expects the Senate Armed Services Committee to hold a series of hearings on the issue in February.

He said he had planned to hold the hearings, with military leaders and outside witnesses, in January but had been asked by the White House to wait until after the State of the Union address.

The ban, also known as Don’t Ask, Don’t Tell, was implemented by President Bill Clinton as a compromise on allowing gays and lesbians to join the military.

It means servicemembers cannot reveal their sexual orientation and senior officers cannot ask them about it. However, an estimated 13,000 troops have been fired under the law, due to outing themselves or being outed by others.

Opponents to lifting the ban argue that it will harm military cohesion and dissuade new recruits.