S. Korean leader to visit US in May

Obama invited Park to visit and "we look forward to welcoming her to the White House in May," national security advisor Tom Donilon said in a speech at The Asia Society in New York.

Donilon has just returned from Seoul, a visit during which he stressed the US administration's "unwavering commitment to the defense of the Republic of Korea."

Park, who was only sworn in two weeks ago, "gave her full support to modernizing our alliance and continuing the effort to partner on a wide range of regional and global issues," he added.

On Monday, she held her first cabinet meeting with her new, still partially-formed administration facing a growing crisis with North Korea.

Since she was sworn in two weeks ago as the country's first woman president, Park has struggled to form a cabinet, with a parliamentary row delaying confirmation of key ministerial nominees.

With North Korea threatening "all-out war" and announcing the scrapping of inter-Korean peace agreements, Park is still without a confirmed defense minister, national security adviser and intelligence chief.

Park had campaigned on a promise of greater engagement with Pyongyang, but her plans have been undermined by the fallout from the North's successful long-range rocket launch in December and its third nuclear test last month.

North Korea has sharply escalated war threats over resulting UN sanctions and a joint South Korean-US military drill that began Monday .

"In Japan and South Korea, the United States can look to new leaders who are firmly committed to close security cooperation with the United States," Donilon said in his speech.

But he added "it is clear that, as we look forward, maintaining security in a dynamic region will demand greater trilateral coordination from Japan, Korea and the United States."