"North Korea will receive relief only when it demonstrates verifiable and irreversible steps to denuclearization," Mattis said at the opening of trilateral talks between the United States, South Korean and Japan on the sidelines of the Shangri-La Dialogue security forum in Singapore.
These words echo the statement of the US Secretary of State Mike Pompeo, who said in May that Washington plans to allow private investments and provide "sanctions relief" if the North Korean government dismantles its nuclear arsenal.
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A historic inter-Korean summit in the truce village of Panmunjom on April 27 prompted a thaw in the relations with Washington, and US President Donald Trump then agreed to meet with Kim in Singapore on June 12 to discuss the situation on the peninsula and possible sanctions relief in exchange for denuclearization.