A group of UN human rights experts has urged Yemen's Houthis to free all prisoners from the country's Bahai religious minority following an earlier decision by the rebels to pardon their jailed leader and drop all charges against other detainees.

There have been concerns about the treatment of Bahai prisoners by the rebels, who have controlled much of northern Yemen and the capital, Sanaa, since the country's civil war started in 2014.

Late last month, senior rebel official Mehdi Al Mashat announced in a televised speech that he had ordered the release of Baha’i leader Hamed bin Haydara, and another five Baha’i detainees. However, the decision has not been implemented.

“We strongly recommend against any rollback of the official decision to pardon and release which was communicated unequivocally,” said the independent experts from the Special Procedures of the Human Rights Council.

Such a reversal, the statement added, “would violate the fundamental rights of those affected”.

Anthony Vance, director of the US Bahai Office of Public Affairs backed the UN's call, saying members of the community held by the rebels must be released "immediately and without conditions".

"It’s surprising that orders from the President of the Houthi Supreme Political Council could be willfully ignored for so long," Mr Vance said. "If the Houthi authorities wish to be respected by the international community, they must respect human rights and uphold commitments made by their leadership. "

A Houthi court sentenced Mr bin Haydara to death for espionage and apostasy in 2018 and his appeal was turned down last month. The rebels are holding 24 other members of the community on similar charges.

The Bahai community says Mr bin Haydara was beaten and given electric shocks in prison and forced to sign documents while blindfolded.

For years, human rights advocates have decried what they say is unlawful incarceration of the Bahais and have demanded the minority be granted the right to practise its faith freely. The monotheistic Bahai religion was founded in 1844 by a Persian nobleman, considered a prophet by followers.