US senators have rejected attempts to open a debate on a bill which proposed lifting the ban on openly gay people serving in the US military.
Just 56 senators voted in favour of debating the defence authorisation bill, four short of the 60 required.
Gay people can serve in the military, but face expulsion if they reveal their sexuality. US President Barack Obama has promised to scrap the policy.
Democrats could still try again later this year to pass the legislation.
Opponents say repeal of the "don't ask, don't tell" law could adversely affect morale in the armed forces.
Earlier, the only Republican senator to support repealing the law, Susan Collins, now said she was withdrawing her support.
Her vote was seen as the crucial 60th vote needed to limit debate and advance the bill in the 100-seat Senate.
BBC News
