New fiery rhetoric from Pyongyang comes as Trump visits the region to try to broker another summit with Kim Jong Un.

North Korea issued new warnings to the U.S. on Thursday, blasting recent statements by Secretary of State Mike Pompeo and threatening military action if diplomacy between Washington and Pyongyang continues to falter.

A statement from North Korea's foreign ministry said the U.S. "viciously slandered" the country, citing the recent release of State Department reports about human trafficking and religious freedom that rank North Korea poorly, and Pompeo's comments on Sunday reiterating that 80 percent of North Korea's economy remains under U.S. sanctions.

"It would be difficult to look forward to the improvement of bilateral relations and denuclearization of the Korean peninsula as long as American politics are dominated by the policy-makers who have an inveterate antagonism towards the DPRK," the statement read, using North Korea's preferred acronym for itself. "If anyone dares to trample over our sovereignty and the right to existence, we will never hesitate to pull a muscle-flexing trigger in order to defend ourselves."

Cartoons on North Korea

Earlier this week, officials from both countries confirmed North Korean leader Kim Jong Un sent President Donald Trump a letter that North Korea's state news service described as "of excellent content." Neither side disclosed any additional details about the letter's contents.

Thursday's statement, however, blasted Pompeo for "sophistry" and said that his comments are "full of falsehoods and fabrications." North Korean officials have previously said they will no longer negotiate with Pompeo, accusing him of "talking nonsense" and being "reckless." Pompeo has responded that the North Koreans don't get to decide the composition of the U.S. delegation.

The latest rhetoric comes at a low point in diplomatic relations between the two countries following two summits the Trump administration organized, one in June 2018 and another in February, which ended abruptly. Both failed to secure any sort of meaningful progress toward denuclearizing the Korean Peninsula in exchange for easing U.S. sanctions. Each side insists the other must act first.

And it follows other new signs that whatever goodwill the Trump administration was able to develop with the Kim regime is deteriorating rapidly.

In May, North Korea test-fired short-range missiles, which Trump dismissed shortly afterward as not "anything major." His assessment differed from those of some of his top officials, including then-acting Defense Secretary Patrick Shanahan who believed the tests violated U.N. resolutions.