Northern Ireland Health Minister Edwin Poots has been ordered to release advice from the country’s attorney general, which he used to justify a lifetime ban on gay men giving blood.

Mr Poots, a born-again Christian who disapproves of same-sex relationships, said it was taken purely on health grounds to prevent the spread of sexually transmitted diseases.

But in February, David Scoffield QC accused Mr Poots of making a “knee-jerk” decision. “We say that the maintenance of the ban represents unlawful discrimination against homosexual men, principally on the basis of their sexual orientation as compared to heterosexual men,” he said.

The Rainbow Project requested the information under the Freedom of Information Act and took their case to the Commissioner’s Office after refusal by Northern Ireland’s Department of Health.

Northern Ireland’s Information Commissioner has ruled that public interest in releasing the advice outweighs the minister’s claim for an exemption.

The Commissioner’s Office has set a release date of 29 April for the minister to comply.

Mr Poots can appeal the decision and ask for it to be reconsidered by a tribunal.

In 2011, England, Wales and Scotland introduced a one-year deferral for gay and bisexual men who wish to donate blood.

They can donate – providing they refrain from having sex with men for 12 months.

However, Mr Poots opted to maintain the lifetime ban in Northern Ireland.

Last year, LGBT campaigners branded Mr Poots “unfit for office” over his decision to challenge a senior judge’s ruling on adoption rights for couples in civil partnerships.

Belfast High Court ruled last October that Northern Ireland’s ban had discriminated against same-sex couples in civil partnerships and also breached their right to family life.