France's new Socialist government Tuesday outlined the broad parameters of its plan to introduce gay marriage and adoption, a key election campaign pledge.

The new law "will extend to members of the same sex the current arrangements of marriage," Justice Minister Christiane Taubira told La Croix newspaper.

"We will open adoption to homosexual couples," she said. "They will be able to adopt children either as individuals or as a couple."

A number of European nations allow gay marriage, but not France, where only married couples and not civil union partners can adopt.

European nations including Belgium, Denmark, Finland, Germany, Iceland, the Netherlands, Norway, Spain, Sweden and Britain allow gay adoption.

Taubira said the new laws would allow "homosexuals wanting to become a 'parent' of their partner's biological child to do so in similar conditions as heterosexuals."

Prime Minister Jean-Marc Ayrault had said in July that gay couples in France will be allowed to get married and to adopt children from next year.

"Our society is evolving, lifestyles and mentalities are changing," he said in a speech outlining the government's agenda. "The government will respond to that."

The Catholic church in France has stressed its opposition to the plan. But on Tuesday the Archbishop of Paris, Cardinal Andre Vingt-Trois, said: "If the republic changes the law, we will observe it".

Opinion polls suggest the church's stance is out of sync with the views of most French people, nearly two-thirds of whom back gay marriage.

Christine Boutin, the leader of France's Christian Democratic Party on Tuesday called for a referendum on the proposal.