North Korea has not responded to behind-the-scenes diplomatic outreach since mid-February by President Joe Biden's administration, including to Pyongyang's mission to the United Nations, a senior Biden administration official told Reuters on Saturday.
The disclosure of the so-far unsuccessful U.S. outreach, which has not been previously reported, raises questions about how Biden will address mounting tensions with Pyongyang over its nuclear weapons and ballistic missile programs.
It also adds a new dimension to a visit America's top diplomat and defense secretary will make this week to South Korea and Japan, where concerns over North Korea's nuclear arsenal are expected to be high on the agenda.