U.S. Secretary of State Mike Pompeo said on Tuesday the Trump administration was "hopeful" North Korea will continue to work toward denuclearization and refrain from long-range missile tests, as Pyongyang's deadline for Washington to reconsider its approach to talks looms.

Speaking at a joint news conference with Russian Foreign Minister Sergey Lavrov, Pompeo also said Washington was looking for ways to talk to Pyongyang but offered no signs that the two sides were any closer to returning to the negotiating table.

North Korean leader Kim Jong Un has set a year-end deadline for the United States to be more flexible in denuclearization negotiations or risk Pyongyang taking a "new path."