The head of the United Nations peacekeeping mission in Mali has called for implementation of a peace agreement signed last year between the government and separatists.

On Thursday, Mahamat Saleh Annadif visited the site of a militant attack in the northern town of Gao. Al Qaeda in the Islamic Maghreb claimed responsibility for the attack, which killed one Chinese peacekeeper and three civilians.

Annadif said an effective implementation of the peace accord is the best way to fight terrorists and to isolate them. The peacekeeping mission in Mali was established in April 2013 after Tuareg separatists and Islamist militants began a rebellion in the desert north.