Admiral Harry B Harris, Jr, Commander, United States Pacific Command delivers his speech on "Challenges, Opportunities, and Innovation in the Indo-Asia-Pacific" at the 30th International Institute for Strategic Studies (IISS) Fullerton Lecture in Singapore on October 17, 2017. / AFP PHOTO / Roslan RAHMAN        (Photo credit should read ROSLAN RAHMAN/AFP/Getty Images)
Washington CNN  — 

President Donald Trump announced his intent to nominate Adm. Harry Harris as US ambassador to South Korea on Friday, filling a key diplomatic post ahead of his high-stakes June 12 meeting with North Korean leader Kim Jong Un in Singapore.

The position has thus far been unfilled in the administration. Trump’s previous choice for the post, Victor Cha, was dropped in January following a disagreement over the White House’s consideration of a pre-emptive strike against North Korea.

The move was expected as Harris had been tapped as ambassador to Australia, but in April, two sources with knowledge of the matter told CNN that then-Secretary of State nominee Mike Pompeo made the suggestion to the President.

Harris is currently the top US military officer overseeing military operations in Asia, as commander of the US Pacific Command.

During his tenure at Pacific Command, Harris has not minced words about North Korea’s ambitions.

US forces in the Pacific “must be prepared to fight tonight, so I take him at his word,” he said last year about Kim’s intentions. “I must assume his claims are true – I know his aspirations certainly are.”

Harris has also watched as an increasingly assertive China has pursued a more muscular military posture in the Pacific and established a military presence on man-made islands in areas the US and its allies contend are international waters.

CNN’s Elise Labott, Nicole Gaouette, Jeremy Herb and Zachary Cohen contributed to this report.