In the first time the Queen has voiced support for gay rights in her 61-year reign, she is set to sign a new charter which aims to tackle homophobic discrimination.

At what will be her first public appearance since leaving the hospital where she was treated for gastroenteritis, the Queen will sign a new Commonwealth Charter, and will make an address explaining her commitment to it.

During the live television broadcast, Queen Elizabeth II, will, in what is being described as a “watershed” moment, signal her support for gay rights, a well as gender equality, and the charter which aims to boost human rights across the Commonwealth.

The charter reads: “We are implacably opposed to all forms of discrimination, whether rooted in gender, race, colour, creed, political belief or other grounds.”

The “other grounds” clause in the charter is intended to refer to sexuality, however specific references to gay and lesbian people were omitted due to some Commonwealth countries with anti-gay laws, reports the Daily Mail.

The Queen is expected to refer to rights which must “include everyone”, and insiders are noting the appearance as a nod to inclusivity.

A diplomatic source said: “The impact of this statement on gay and women’s rights should not be underestimated. Nothing this progressive has ever been approved by the United Nations. And it is most unusual for the Queen to request to sign documents in public, never mind call the cameras in.”

A spokesperson for Buckingham Palace, said: “In this charter, the Queen is endorsing a decision taken by the Commonwealth.” But he added: “The Queen does not take a personal view on these issues. The Queen’s position is apolitical, as it is on all matters of this sort.”

Prior to tomorrow’s appearance, the Queen has been in talks with Commonwealth Secretary-General Kamalesh Sharma, who has led the initiative. Last month, he said: “We oppose discrimination or stigmatisation on any grounds.”

Royal aides have also been in discussion with Foreign Secretary William Hague, who has backed the drive for better gay rights, and gender equality.

Gay rights advocates have voiced strong opinions in the past, on the fact that the Queen is a patron of over 600 charities, however none of them are for gay rights. Queen Elizabeth II has never publicly voiced her support of equal rights for gay people.

Ben Summerskill of Stonewall, said the Queen had taken “an historic step forward” on gay rights, and said “The Palace has finally caught up with public opinion.”

He also said it was significant that the Queen was publicly acknowledging “the importance of the six per cent of her subjects who are gay. Some of the worst persecution of gay people in the world takes place in Commonwealth countries as a result of the British Empire.”

Welsh Conservative MP David Davies said: “I fail to see why the Queen needs to make a special statement on this country’s opposition to discrimination against gays and women. It is a statement of the blindingly obvious.

“My worry is the politically correct brigade will use it to silence legitimate debate about issues like gay marriage. One can’t help wondering what Prince Philip’s view would be.”

Davies, who recently suggested most parents would prefer their children “not to be gay”, dismissed accusations that he is a homophobe by reminding people of his participation in an amateur boxing match against a gay fighter.

Homosexual acts are illegal in 41 of the 54 Commonwealth nations, and penalties include the death sentence in parts of Nigeria and Pakistan, 25 years in jail in Trinidad and Tobego, 20 years plus flogging in Malaysia and life imprisonment in Sierra Leone, Tanzania, Uganda, Bangladesh and Guyana.

Only five Commonwealth countries recognise same-sex relationships: the UK, Australia, Canada, New Zealand and South Africa.

The charter, to be signed at London’s Marlborough House, Pall Mall, is not directly linked to the issue of accession, the Queen’s acceptance of it could signal a change in Royal accession rights for males and females.

Before making her address, the Queen will celebrate the charter in a service at Westminster Abbey, where she will be joined by singer Beverly Knight, rock band the Noisettes and Sir Richard Branson.

Beverly Knight has in the past spoken out against the blatant homophobia in a great deal of music from black artists including Beenie Man.

In May 2012, the founder of the Virgin Group, Sir Richard Branson, became the most high profile figure at that point to film a video for the Out4Marriage campaign, which calls for global equal marriage for gay couples.