LONDON -- New Zealand and Britain became on Monday the latest countries to ease rules on blood donations by gay and bisexual men, as supply concerns caused by COVID-19 increase scrutiny of AIDS pandemic-era restrictions that LGBT+ rights advocates say are homophobic.

New Zealand's government cut the celibacy period for gay and bisexual men to give blood from a year to three months, regardless of whether or not they had used condoms, the New Zealand Blood Service said on its website on Monday.

In Britain, which had a three-month deferral period, a behavior-based policy will be used from mid-2021, meaning anyone - gay or straight - who has had anal sex with multiple partners or a new partner will not be able to donate blood.

The change means men in long-term gay monogamous relationships will be eligible to donate blood without any waiting period from "summer 2021," a statement on a government website said on Monday. https://www.blood.co.uk/news-and-campaigns/news-and-statements/fair-steering-group/

A spokeswoman for England's state blood donation service said she could not give an exact date for the implementation.

"It's groundbreaking. It's a fundamental shift away from stereotyping sexuality to assessing individual risks," said Ethan Spibey, the founder of campaign group Freedom to Donate, which worked with the government on the new policy.

Restrictions on gay men donating blood, imposed by many countries at the height of the HIV/AIDS pandemic in the 1980s, have faced renewed scrutiny this year amid concerns about maintaining supplies of blood during the coronavirus crisis.

Lockdowns have made it harder for potential donors to access donation centers.

The United States reduced its waiting period for gay and bi men from a year to three months in April. Australia said it would follow suit the same month, although the change will not apply until Jan. 31 2021.

LGBT+ campaigners criticized both countries, however, saying the policies continued to discriminate against gay and bi men.

Some activists leveled similar criticism against the new British policy because of its focus on anal sex, which is most commonly associated with gay and bisexual sex.

"We still are not at a point where the sex gay men have and the sex straight people have is equal," said Ash Kotak, a playwright who is campaigning for a London AIDS memorial. "The policy decision is guided by homophobia and fear."

However, Michael Brady, medical director at the HIV charity Terrence Higgins Trust and national LGBT health advisor for England's state health service, said the "anal sex deferral makes sense" based on the available medical evidence.

"Anal sex as an act, irrespective of whether you're gay or straight, is associated with a greater risk of transmission of blood-borne viruses like HIV," Brady, who sat on an advisory committee that recommended the new policy, told the Thomson Reuters Foundation.

Since 2001, Italy has had a risk-based policy that does not consider the type of sex, which has not led to the blood supply being increasingly compromised by HIV infections, researchers at Italy's National Institute of Health said in a 2013 study.

From the Thomson Reuters Foundation, Editing by Helen Popper and Hugo Greenhalgh.