Kremlin spokesman Dmitry Peskov said Friday that Moscow is deeply concerned by the escalation of tension on the Korean Peninsula caused by the continued war of words between the U.S. and North Korea.

He told reporters there is no alternative to “a political and diplomatic settlement of the North Korean problem.”

The spokesman stressed that the situation was being further aggravated by “the swapping of silly statements full of threats.”

US President Donald Trump earlier vowed to “destroy North Korea,” leading Pyongyang to declare that it might test a hydrogen bomb over the Pacific Ocean, Reuters said.