U.S. Secretary of State Mike Pompeo said on Tuesday that the United States is hopeful North Korea will continue to refrain from nuclear and long-range missile tests and work towards denuclearization.

Pompeo made the remarks during a joint press conference with Russian Foreign Minister Sergei Lavrov in Washington.

The secretary said that U.S. President Donald Trump has been "unambiguous" about U.S. expectations after three meetings with North Korean leader Kim Jong-un. 

Pompeo said that Kim personally made the commitment to denuclearize and said there wouldn't be long-range missile or nuclear tests. He added the U.S. is very hopeful that the North Koreans will continue to abide by all of those commitments. 

Pompeo also said that the U.S. is working to develop places and negotiation mechanisms that allow for communication with North Korea and a discussion of paths forward to achieve denuclearization.

The remarks came days after Pyongyang said it had conducted a "very important" test at its west coast space launch facility, raising speculation that it may have tested an intercontinental ballistic missile engine.

[Photo : YONHAP News]