Speaking this morning, she said that new provisions in the Equality Act “explicitly” say that faiths have the right to reject gay couples.
The government announced today that civil partnerships will be permitted in religious buildings and that consultation will begin on marriage equality.
Some faith groups have reacted angrily to the plans and a letter signed by five Christian groups – including the Christian Institute and Christian Concern – reiterated opposition.
It said: “When it comes to equality legislation, permission often turns rapidly into coercion.
“In a country where faith-based adoption agencies have been forced to close or cut their religious ties by equality law, where Christian marriage registrars can be dismissed for their religious views on marriage and where Christian B&B owners are forced to pay compensation to same-sex couples, Christians will need a great deal of reassurance that the government is not about to do something that will make their situation even worse.”
Ms Featherstone said: “Obviously there is a degree of anxiety from some of the religious organisations. In the words of the Act itself, it says explicitly, for the avoidance of doubt, that there is nothing in this Act which placed an obligation on religious organisations to host civil partnerships unless they wish to do so.
“By the same token, it is a step forward for religious freedom in that it gives the Quakers, the Liberal Jews . . . the freedom to do so.”
She added: “We’ve been very clear that we will not force religious organisations to host [civil partnerships] if they do not wish to.
“And nor do we believe that any minister who refused would be successfully sued under discrimination law.”
As well as religious civil partnerships, the government has also announced it will begin consulting on marriage equality.
Marriage equality is the official party policy of the Liberal Democrats and leader Nick Clegg supports a change in the law.
Ms Featherstone said that the plans have the support of the entire government and that there had been no resistance from Tory ministers.
“I am fully supported by all of government over these plans going forward,” she said.
When asked whether full marriage equality could be granted before 2015, she said: “I think that all depends on the consultation and how we work with people.
“Clearly there are some people who absolutely want heterosexual civil partnerships and homosexual civil marriage and that is something we will be examining.”
But she added that plans were still in “very, very early days”.
Ms Featherstone said her own support for marriage equality was “well on the record”.
Stonewall chief executive Ben Summerskill welcomed the announcement on civil partnerships but questioned the government’s commitment to gay marriage.
He said: “If there’s a genuine commitment to making progress in this area, it is painfully slow. Equalities minister Lynne Featherstone has explicitly said she would consult on proposals the government intends to implement in the lifetime of this parliament.”
Ms Featherstone responded: “I’m very pleased that Stonewall are so enthusiastic about the progress and I’m sure they will be supportive of the government moving forward on it.”