Gay and bisexual men who have not had oral or anal sex in the last year are now officially allowed to give blood, according to the UK Department of Health.

This ends Britain's blanket, lifetime ban on gay and bisexual blood donors. It had been in force for nearly 30 years, since the early days of the HIV pandemic in the 1980s.

Although the new policy is a big improvement, the revised rules are still excessive, unjustified and discriminatory.

The 12 month ban is too sweeping and draconian. It applies to men who always use a condom and who test HIV-negative.

The fact is that most gay and bisexual men do not have HIV and will never have HIV. If they always have safe sex with a condom and test HIV negative, their blood is safe to donate. They can and should be allowed to help save lives by becoming donors.

Curiously, there are no similar blanket restrictions on heterosexual men and women who engage in risky sexual behaviour.

The blood service does not, for example, exclude men who regularly travel to cities such as New York, which has a high rate of heterosexually-transmitted HIV infection, and who have vaginal or oral sex with multiple women partners without a condom. The rules smack of double standards.

I have been campaigning for 20 years for an evidence-based policy which protects the blood supply while not needlessly discriminating against men who have sex with men.

Although safeguarding the health of blood donation recipients is the number one priority, ensuring blood safety does not require such a lengthy time span during which gay and bisexual men are barred from donating blood.

The UK blood service could have opted for a much shorter exclusion period. The restrictions should focus on excluding donors who have engaged in risky sexual behaviour and those whose HIV status cannot be accurately determined because of the delay between the date of infection and the date when the HIV virus and HIV antibodies manifest and become detectable in an infected person's blood.

In my view, reducing the exclusion period for blood donations from gay and bisexual men should go hand-in-hand with a number of wider reforms of the blood donation service.

There is a compelling case for a 'safe blood' education campaign targeted at the gay community, to ensure that no one donates blood if they are at risk of HIV and other blood-borne infections due to unsafe sexual behaviour.

We also need a major drive to vaccinate gay and bisexual men against Hepatitis A and B, to protect their health and to prevent these infections getting into the blood supply.

In addition, the questionnaire that would-be blood donors have to answer should be made more detailed for men who've had sex with men, in order to more accurately identify the degree of risk, if any, that their blood may pose. A few additional questions would improve donor awareness of risk factors and more accurately exclude those whose blood may not be safe.

With the adoption of these reforms, most gay and bisexual men would not need to be excluded as donors unless they'd had risky sex without a condom within the preceding six months.

Bizarrely, the blood service's new policy makes no distinction between sex with a condom and sex without one. Any oral or anal sex between men in the previous 12 months - even with a condom - will be grounds for continuing to refuse a donor under the new rules. This is unjustified. If a condom is used correctly, it is absolute protection against the transmission and contraction of HIV. Men who use condoms every time without breakages - and who test HIV negative - should not be barred from donating blood.

With these provisos and safeguards, a shorter exclusion period would be reasonable and not endanger the blood supply. The blood donated would be safe.