Vermont Senator Patrick Leahy on Tuesday filed an amendment to the immigration bill which would protect bi-national gay and lesbian couples.

“Seeking equal protection under our laws for the LGBT community is the right thing to do,” Leahy, a Democrat, said in a statement.

Leahy first introduced the amendment in the Democratic-controlled committee that he chairs. It seeks to allow a gay American to sponsor an immigrant spouse for citizenship, which is currently not allowed pursuant to the Defense of Marriage Act (DOMA). Under threat from Republicans to end their support for the entire bill, Leahy, with a “heavy heart,” withdrew the amendment.

“I withdrew my anti-discrimination amendment during the Senate Judiciary Committee markup. As the entire Senate turns to debate the immigration bill, the fight for equality must go on,” Leahy added.

Steve Ralls, a spokesman for Immigration Equality, which lobbies for the rights of bi-national gay and lesbian couples, applauded the move.

Leahy “has always been at the forefront of the work to ensure our immigration system treats everyone fairly,” Ralls said.

It was unclear whether Leahy would offer the amendment on the Senate floor.