Eight British couples – four gay and four straight – are to launch a legal bid to win the right to gay marriage and straight civil partnerships.

The Equal Love campaign, co-ordinated by gay rights activist Peter Tatchell, will see the eight couples file a joint application at the European Court of Human Rights.

The couples were due to launch their challenge today but it has been delayed because one of the couples were given the wrong documentation after being denied a civil partnership.

According to PA, Camden council mistook straight couple Stephanie Munro and Andrew O’Neil as a gay couple, meaning they did not receive the refusal letter they require for the court case.

In the last two months, the couples have applied for, and been rejected from, civil partnerships and marriages.

Under current UK law, only straight couples can marry and civil partnerships are only open to gay couples.

Mr Tatchell said: “Since there is no difference in the rights and responsibilities involved in gay marriages and heterosexual civil partnerships, there is no point or justification in having two mutually exclusive and discriminatory systems.

“Outlawing black marriages would provoke uproar. The prohibition on gay marriages should provoke similar outrage.

“The bans on same-sex civil marriages and opposite-sex civil partnerships are a 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.”

A recent PinkNews.co.uk poll of 800 readers found that 98 per cent wanted the right to marry. Seventy-seven per cent agreed that marriage and civil partnerships should be open to everyone, while 23 per cent said that marriage should be the only form of recognition for all couples.

A Populus opinion poll for the Times in June 2009 found that 61 per cent of the public believe that ‘gay couples should have an equal right to get married, not just to have civil partnerships’. Only 33 per cent disagreed.