Updated

An international human rights watchdog is calling on Southeast Asian leaders to take a stand against the Philippines' war on drugs that has left thousands dead under President Rodrigo Duterte, the host of this week's regional summit.

Amnesty International says leaders of the 10-member Association of Southeast Asian Nations must consider whether the killings amount to a serious breach of ASEAN's charter, particularly its pledge to human rights.

It says up to 9,000 people have been killed by police or unknown armed persons since July 2016. Officials say not all deaths being reported are drug-related while others were killed in legitimate police operations.