WASHINGTON — The Trump administration on Thursday ratcheted up pressure on North Korea, imposing new sanctions on two Chinese shipping companies that it says have been helping the country evade international sanctions.

The sanctions linked to North Korea were the first that the Treasury Department has imposed since late last year and come less than a month after a summit meeting between President Trump and Kim Jong-un, North Korea’s leader, collapsed in Hanoi, Vietnam, without a deal.

Mr. Trump wanted North Korea to fully denuclearize in exchange for sanctions relief, while North Korea favored a more gradual rollback of its nuclear program in exchange for the removal of sanctions that are most painful to its citizens.

“The United States and our like-minded partners remain committed to achieving the final, fully verified denuclearization of North Korea and believe that the full implementation of North Korea-related U.N. Security Council resolutions is crucial to a successful outcome,” Steven Mnuchin, the Treasury secretary, said in a statement.