The US Food and Drug Administration has decided to retain current rules on gay and bisexual men donating blood.

The body held hearings last week on the issue and committee members voted nine to six against making any immediate changes.

They said there was still a tiny but “unacceptable” increased risk of HIV transmission to blood recipients.

Currently, America bans any man who has sex with another man since 1977 from ever donating blood.

The policy was a reaction to the HIV/AIDS crisis which began in the 1980s.

However, heterosexual men and women who have had sex with a person at risk of HIV must only defer from donating for 12 months.

The committee acknowledged gay men were being treated unfairly and recommended that health agencies should move towards a more nuanced system of screening potential donors.

This would seek to screen out heterosexual donors who have engaged in risky behaviour.

The panel also called for more research into men currently in the banned group and recommended pre-testing of their blood.

It was recently estimated that lifting the US blood ban could provide an extra 219,000 pints a year.

The Williams Institute for Sexual Orientation Law and Public Policy calculated this increase would mean a of 1.4 per cent rise in the nation’s blood supply.

The UK has similarly restrictive laws for gay and bisexual men who want to donate blood, although they are not barred from donating their organs.