Gay rights campaigners have launched a petition to call for gay marriages and straight civil partnerships in the UK.
The Equal Love campaign, led by Peter Tatchell, has already filed a case at the European Court of Human Rights.
Currently the UK allows gay couples to have civil partnerships. But there is a growing push towards full equal rights for gay couples and campaigners say it is also unfair that straight couples cannot get civil partnerships.
Speaking to PinkNews.co.uk, Mr Tatchell said the petition will eventually be presented to prime minister David Cameron. Campaigners hope to collect at least 15,000 signatures.
Stressing that only UK residents can sign the petition, Mr Tatchell said: “There is no justification for having two mutually exclusive and discriminatory systems.
“The bans on same-sex civil marriages and opposite-sex civil partnerships are a legal form of sexual apartheid – one law for gay couples and another law for heterosexual partners. Two wrongs don’t make a right. In a democratic society, we should all be equal before the law.”
The legal case submitted to the European Court of Human Rights in February involves four gay couples and four straight couples – each of whom attempted to register for a ceremony they are not entitled to.
The British government has 12 months in which to justify why the ban should remain.
Coalition ministers say they are committed to implementing a permissive amendment to the Equality Act to allow religious buildings to host civil partnerships.
A consultation on the move is taking place now and it is understood that the law could change by the end of the year.
Equality minister Lynne Featherstone said in February that a separate consultation will be held on opening up marriage and civil partnerships to everyone.
Speaking at a Stonewall event in March, home secretary and secretary of state for equalities Theresa May said: “There is also a desire to move towards equal civil marriage and partnerships and we will consult further on how legislation can develop, working with all those who have an interest in this area.”