ISTANBUL (AP) — Turkey has withdrawn from a landmark European treaty protecting women from violence that it was the first to sign 10 years ago and that bears the name of its largest city.

President Recep Tayyip Erdogan’s decree early Saturday annulling Turkey’s ratification of the Istanbul Convention is a blow to women’s rights advocates, who say the agreement is crucial to combating domestic violence.

Violence against and killing of women is on the rise in Turkey, according to rights groups.

A total of 77 women have been killed since the start of the year, according to the We Will Stop Femicide Platform. At least 409 women were killed in 2020, according to the group.

Some officials from Erdogan’s Islam-oriented party have advocated a review of the agreement, claiming it encourages divorce and promotes LGBT culture which they say are contrary to the country’s conservative values.

Turkey was the first country to sign the Council of Europe’s “Convention on preventing and combating violence against women and domestic violence” at a committee of ministers meeting in Istanbul in 2011. The law came into force in 2014.

The Istanbul Convention states that men and women have equal rights and obliges state authorities to take steps to prevent violence against women, protect victims and prosecute perpetrators.