PARIS - French President Francois Hollande has signed into law a bill allowing same-sex marriage, making France the 14th country to legalise gay weddings.

France's official journal announced on Saturday that the bill had become law after the Constitutional Council gave the go-ahead on Friday.

The bill, a campaign pledge by the Socialist president, has been hotly contested in France where allowing gay marriage is one of the biggest social reforms since abolition of the death penalty in 1981.

Opponents have staged huge and often violent demonstrations against the bill and have called yet another protest on May 26. The first marriage under the law is due to be held in Montpellier in southern France on May 29.

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 D.C. and 12 states have legalised same-sex marriage.