The United States is taking it as a "good sign" that North Korean leader Kim Jong Un recently sent a "get-well" note to U.S. President Donald Trump after he contracted the novel coronavirus, a senior U.S. diplomat said Thursday.

"It's a good sign, I suppose, that Chairman Kim is watching and expressing concern about our leader," Marc Knapper, deputy assistant secretary of state for Korea and Japan, said at an online think tank event, noting that Pyongyang has not publicly expressed sympathy toward Washington over any issue since the Sept. 11, 2001, terrorist attacks.

North Korean leader Kim Jong Un and U.S. President Donald Trump at the demilitarized zone (DMZ) separating the South and North Korea on June 30, 2019. (KCNA/Kyodo)

Knapper also said the United States remains open to dialogue with North Korea in the hope of actualizing the denuclearization goals laid out by Trump and Kim following their first-ever summit in Singapore in 2018.

At the summit, Trump promised Kim that Washington would provide security guarantees to Pyongyang in return for "complete" denuclearization of the Korean Peninsula.

Trump has met Kim twice since then, but talks have shown little progress, with the two countries at odds over issues such as the degree of sanctions relief Pyongyang should receive for denuclearization steps.

On Saturday, Kim sent a message to Trump over his contracting of the coronavirus, offering "sympathy" and expressing wishes for speedy recovery by the U.S. president and the first lady, who has also tested positive, according to North Korea's official Korean Central News Agency.

The report came a day after Trump, 74, announced that he and his wife Melania, 50, had tested positive for the virus that causes the respiratory illness COVID-19. The couple have been recovering.

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