Equality minister Lynne Featherstone has announced that the government's consultation on gay marriage is postponed until March, and that its terms of reference will explicitly exclude same-sex religious marriages and opposite-sex civil partnerships.

It is perplexing that the minister for equality wants to maintain discriminatory laws that prohibit gay couples from having a religious marriage and heterosexual couples from having a civil partnership.

Given that the government has no plans to scrap civil partnerships, Featherstone is wrong to rule out in advance any discussion on opening them up to opposite-sex couples. Many heterosexuals would like a civil partnership. Denying them this option is unfair – and illegal under human rights law. How can the equality minister support this?

France and the Netherlands have an equivalent to civil partnerships, respectively PACS and registered partnerships. They are open to same-sex and opposite-sex couples. The vast majority of civil partnerships in these countries are heterosexual ones. They are hugely popular, and would be equally popular here if the government allowed straight couples to have them.

The government's proposed continuation of the ban on religious gay marriages is another surprise. It is an infringement of religious freedom to dictate to faith organisations what they can and cannot do. Some religions – such as the Quakers, Unitarians and liberal Judaism – want to conduct same-sex marriages. The equality minister says they will not be allowed to do so.

While no religious body should be forced to perform gay or lesbian marriages, the government should support an end to the legal prohibition on same-sex weddings conducted by faith organisations.

The consultation on gay marriage was supposed to begin in June. There is no excuse for postponing it. Why can't it start now? In fact, why do we need consultation at all? The ban on same-sex marriage is homophobic discrimination and should be repealed immediately.

No other legislation is subjected to such prolonged consultation. The Scottish government's consultation on marriage equality began this month. Why is the UK dragging its feet? If Muslim or Jewish people had been banned from marriage, the government would act swiftly to end such discrimination.

Ending sexual orientation discrimination in marriage law is the right thing to do and it has majority public support. According to a 2009 Populus opinion poll, 61% of the public believe that lesbian and gay couples should be allowed to get married.

Despite the government's assurances, there is a serious danger the delay will prevent marriage equality coming to pass before the next election. Because the consultation will not begin until March, it is unlikely that legislation will be presented to parliament before mid-2013. Allowing for obstruction by the Lords, it is doubtful that it would be passed before late 2014, which is perilously close to the next election. If the prime minister called an early poll, the legislation would fall.

This raises a question: is the consultation an attempt to kick same-sex marriage into the long grass? Featherstone's announcement is clearly an attempt to thwart the Equal Love legal case in the European court of human rights, where four gay couples and four heterosexual couples are seeking to overturn discrimination in civil marriage and civil partnership law. She won't succeed. We are confident that the government's decision to retain the prohibition on opposite-sex civil partnerships will be ruled illegal. Featherstone should think again.