PARIS (REUTERS) - France's Constitutional Council cleared the way on Friday for same-sex marriage, throwing out a last-ditch effort by opponents to scupper the country's biggest social reform since abolition of the death penalty.

After months of sometimes violent street demonstrations, the Council gave the go-ahead to a law that will make France the 14th country to legalise gay weddings, in line with an election promise by Socialist President Francois Hollande.

Mr Hollande has promised to rapidly sign a bill that lawmakers adopted in late April, raising the prospect that the first gay weddings in France could take place within weeks.

"The law allowing same-sex marriage conforms with the constitution," the council said in a statement.

While late Socialist President Francois Mitterrand braved opposition by most French people to abolish the death penality in 1981, polls show more than half the country backs Mr Hollande's move to allow couples of the same sex tie the knot.

France, a predominantly Catholic country, follows 13 others including Canada, Denmark, Sweden and most recently Uruguay and New Zealand in allowing gay and lesbian couples to wed. In the United States, Washington DC and nine states have legalised same-sex marriage.