FILE PHOTO: U.S. Special Representative for North Korea Policy Joseph Yun (R) answers questions from reporters at the Iikura guest house in Tokyo, Japan April 25, 2017. REUTERS/Toru Yamanaka/Pool/File Photo

WASHINGTON (Reuters) - The U.S. envoy for North Korea will travel to Japan and Thailand next week to discuss how to increase pressure on Pyongyang after its latest ballistic missile test, the U.S. State Department said on Friday.

North Korea, formally called the Democratic People’s Republic of Korea (DPRK), last week tested its most powerful intercontinental ballistic missile (ICBM), saying the device could reach all of the United States.

Joseph Yun, the U.S. special representative for North Korea policy, will travel to Japan and Thailand Dec. 11-15 to meet government officials “to discuss ways to strengthen the pressure campaign following the DPRK’s latest ballistic missile test,” the State Department said in a brief written statement.

“The United States looks forward to continuing its partnership with both these nations so that the DPRK will return to credible talks on denuclearization,” it added.

Tensions have risen markedly in recent months over North Korea’s development, in defiance of repeated rounds of U.N. sanctions, of nuclear-tipped missiles capable of reaching the United States.

Last week’s missile test prompted a U.S. warning that North Korea’s leadership would be “utterly destroyed” if war were to break out. The Pentagon has mounted repeated shows of force after North Korean tests.

The United States has sent mixed signals about its interest in talks with the North, with Secretary of State Rex Tillerson saying that Washington was pursuing such contacts but President Trump tweeting that this was a waste of time.