It is the strongest response yet from the elderly leader about the Oct 26 agreement which has angered the Malaysian public.

Vietnam was the world's third-largest rice exporter last year after India and Thailand, and the Philippines is its largest buyer.

Indonesia, chair of the 10-member Asean, is expected to symbolically hand over the chair to Laos, though it will maintain the role until the end of the year.

China suspended barley imports from CBH Grain, a subsidiary of CBH Group, in late 2020 after allegedly finding quarantine pests in cargoes.

Relations between the trade partners deteriorated in 2020 after Australia called for an inquiry into the origins of Covid-19, triggering reprisals by Beijing including anti-dumping duties on Australian wine and barley.

PNG, which counts China as a major trading partner, signed a defence cooperation agreement with the US during the Blinken visit.

More than two years after China first slapped tariffs and unofficial bans on a range of commodities including coal and barley, Beijing has begun removing restrictions.

However, they promise to keep lines of communication open.

The pair will also chair a Joint Ministerial Economic Commission, a meeting first held in 1986, but suspended since 2017 when ties began to deteriorate over diplomatic disputes.

The two leaders announce that negotiations will begin on giving EU producers of critical minerals access to the US market under Biden's signature programme to encourage climate friendly industries.

The isolated country has suffered food shortages in recent years, reeling from floods and typhoons, international sanctions aimed at curbing its nuclear and missile programmes, and a sharp cut in trade.

Finance Minister Choo Kyung-ho says the reopening of South Korea's giant neighbour from long lockdowns would help improve foreign trade in the coming months.