Britain said Thursday it was lifting a ban on gay men giving blood providing they have had not had homosexual intercourse within a year.
A lifetime ban on blood donation by men who have had sex with another man was introduced in Britain in the 1980s as a response to the spread of AIDS and HIV.
But a review by a panel of leading experts and patient groups found it could no longer support their permanent exclusion.
However, men who have had anal or oral sex with another man in the past 12 months, with or without a condom, will still be barred from donating blood, the Department of Health said.
The experts considered the risk of infection being transmitted through blood, the willingness of potential donors to comply with the selection criteria and improvements in testing donated blood.
The change brings the criteria for men who have had sex with men into line with other groups who are deferred from giving blood for 12 months due to infection risks associated with sexual behaviour.
These include women who have slept with a man who has had sex with another man, people who have slept with prostitutes and those who have had intercourse with anyone who has injected themselves with drugs.
The announcement was welcomed by human rights campaigner Peter Tatchell, but he said it fell short of lifting the ban on gay men who always use condoms.
He said: "Although the new policy is a big improvement on the existing discriminatory rules, a 12-month ban is still excessive and unjustified."
Tatchell, who launched the first campaign against the lifetime ban in 1991, added: "Most gay and bisexual men do not have HIV and will never have HIV.
"If they always have safe sex with a condom, have only one partner and test HIV negative, their blood is safe to donate.
"They can and should be allowed to help save lives by becoming donors."