Human rights campaigner Peter Tatchell is calling on the London Organising Committee of the Olympic and Paralympic Games to ban anti-gay countries from the events this summer.

Mr Tatchell said: “The Olympic Charter prohibits all discrimination, and this includes homophobic discrimination. Any country that discriminates against women, ethnic or religious minorities, or lesbian, gay, bisexual and transgender (LGBT) athletes should be disqualified from the 2012 Olympics.”

The Olympic Charter states: “Any form of discrimination with regard to a country or a person on grounds of race, religion, politics, gender or otherwise is incompatible with belonging to the Olympic Movement.”

Mr Tatchell, director of the human rights organisation the Peter Tatchell Foundation said: “Why isn’t homophobia, biphobia and transphobia being challenged by the Olympic authorities? It is wrong that in over 150 countries LGBT athletes are forced to hide their sexuality in order to get selected and compete.”

“The International Olympic Committee and London Olympic organisers should require all competing nations to sign a pledge that they do not discriminate on the grounds of gender, ethnicity, religion or sexual orientation. If they refuse to sign, they should be denied participation in the games.

“I appeal to Olympic chiefs, Jacques Rogge and Lord Coe, to make a public statement that LGBT athletes are welcome at London 2012 and that participating nations must not discriminate on the grounds of sexual orientation or gender identity. We need a signal from the top that homophobia and transphobia are contrary to the Olympic spirit and Charter.”

PinkNews.co.uk has approached the Committee for a response.

Mr Tatchell said discriminated-against groups faced a lack of access to sporting facilities, competitions and the Olympic selection process on the basis of religion, race, sexuality and gender.

He added: “It would be impossible for an openly gay athlete to be selected for the Olympic squad of most countries. They would face rejection because of their sexual orientation and, in many caes, imprisonment.”

“Over 150 nations have legal systems that, in the absence of laws against homophobic discrimination, permit victimisation and bias against LGBT citizens and athletes.

“The government of Saudi Arabia provides almost no sports opportunities for women. It has selected only one token women athlete to compete in the London Olympics. Iran practices systematic discrimination against its Kurdish, Arab and Baluch citizens. India’s dalits (so-called untouchables) are, in effect, Olympic outcasts.

Mr Tatchell said the Olympics should be “open to everyone, based solely on merit and without discrimination”.

He concluded: “The International Olympic Committee (IOC) and London Organising Committee for the Olympic Games (LOCOG) have, so far, failed to ensure that all competing nations comply with the non-discrimination clauses of the Olympic Charter. It is not too late for them to do so. It’s their duty to uphold the Olympic Charter.”

The opening ceremony for the London Olympics, formally the Games of the XXX Olympiad, will take place on 27 July.