South Korean President Moon Jae-in and other officials will meet US counterparts in a bid to jump-start stalled denuclearisation talks with North Korea.
Moon will hold a summit meeting with President Donald Trump in Washington on April 11 to discuss North Korea and other alliance issues, the White House said on Friday.
"The alliance between the United States and the Republic of Korea remains the linchpin of peace and security on the Korean peninsula and in the region," it said in a statement.
The second summit between Trump and North Korean leader Kim Jong-un fell apart in Hanoi in February over differences about the limits on Pyongyang's nuclear programs and US willingness to ease sanctions.
The Hanoi summit's breakdown hit rapidly improving ties between the neighbours. South Korea's defence ministry said it proposed military talks with the North last week but there was no response from Pyongyang.
Trump's failure to seal a deal was a blow to Moon, who has been vocal in his conviction that Kim is willing to abandon his nuclear arsenal.
Washington and Seoul have also tussled over the cost of US troops in South Korea, with Trump demanding that Seoul pay more toward maintaining some 28,500 of them.
The North has nearly completed work to rebuild its Sohae missile launch site in the northwestern town of Tongchang-ri that Kim, at his first summit with Trump last June, had vowed to dismantle, South Korean lawmakers said on Friday.
Ahead of the Trump-Moon summit, South Korea said it was sending its foreign and defence ministers, and other senior officials, to meetings in Washington.
Last week the North also pulled out of a liaison office with South Korea agreed during Moon's summit with Kim, only to reverse the move and send back some officials three days later.
