Prime Minister Shinzo Abe will make a three-day trip to Thailand from Sunday to attend a series of summits related to the Association of Southeast Asian Nations, including one to negotiate a region-wide free trade deal, the government said.

During his stay in Bangkok, Abe is scheduled to take part in a summit with five Southeast Asian countries along the Mekong River — Cambodia, Laos, Myanmar, Thailand and Vietnam — Chief Cabinet Secretary Yoshihide Suga said at a news conference Friday.

On Monday, Abe is expected to attend a leaders' meeting for the Regional Comprehensive Economic Partnership, a free trade deal under negotiation that involves the 10 ASEAN members plus Australia, China, India, Japan, South Korea and New Zealand.