North Korea's foreign ministry said Tuesday that now is not the appropriate time to discuss the fate of US citizens the country is holding.

The ministry announcement, released by the Korean Central News Agency, stressed the circumstances surrounding the present North Korea-US relations as not conducive to negotiations.

Both countries have been ratcheting up their war of words, with Pyongyang and Washington both threatening military action against the other side.

The statement also comes after foreign media claimed that the US delegate on North Korean affairs, Joseph Yun, met with  North Korean diplomats assigned to the United Nations through the so-called New York channel. The talks were centered on the release of US citizens held in the reclusive country, the report said, citing an anonymous source.

On the matter of releasing prisoners, Pyongyang last week did set free a Canadian pastor suffering from poor health. It earlier freed US college student Otto Warmbier after he fell into a coma following a 17-month detention. Warmbier died a few days after being medically evacuated back home.

There are currently three US nationals, all Korean-American -- being held by Pyongyang for "serious offenses" committed against the North.

Washington, meanwhile, barred its citizens from traveling to North Korea starting Sept. 1 unless they have a special reason to do so. (Yonhap)