By Hyonhee Shin
SEOUL (Reuters) -South Korean President Yoon Suk Yeol will visit the United States next week for a summit with President Joe Biden as the allies grapple for ways to handle the challenge posed by North Korea's growing nuclear and missile arsenal.
Yoon's April 24-29 trip will be the first state visit to the United States by a South Korean leader since 2011 and will mark the 70th anniversary of the countries' alliance.
The two leaders are expected to discuss joint responses to deter North Korea, partnerships to build more stable supply chains and expanding cooperation on chips, batteries and other high-tech areas.
"It will be an opportunity to further solidify the combined defence posture and operate extended deterrence between the two countries in a more concrete manner, while deepening economic security cooperation," deputy national security adviser, Kim Tae-hyo, told a briefing.
Tension has flared on the Korean peninsula since the conservative Yoon took office in May last year, replacing a liberal president who had tried to promote negotiations with North Korea.
North Korea has ramped up the development of weapons, testing its first solid-fuel intercontinental ballistic missile last week, the latest in a series of tests.
North Korea says it needs its weapons to protect itself from plans by South Korea and the U.S. for "regime change". South Korea and the United States deny any such intention.
Yoon has been pushing to boost South Korea's role in operating what is known as U.S. extended deterrence, the American nuclear umbrella protecting its allies.
Yoon and Biden are also likely to consult on how to support Ukraine, amid mounting Western pressure for South Korea to help it battle Russian forces.
South Korea, a major producer of artillery ammunition, has tried to avoid antagonising Russia, due largely to commercial interests and Russian influence over North Korea, focusing instead on humanitarian and financial aid for Ukraine.
Yoon, in an interview with Reuters on Tuesday, signalled for the first time a softening in his position on weapons to Ukraine, saying his government might not "insist only on humanitarian or financial support" in the event of a large-scale attack on civilians or a "situation the international community cannot condone".
Yoon will hold a summit and a joint news conference with Biden on April 26 and deliver a speech to the U.S. Congress on April 27 before travelling to Boston where he is due to speak at the Harvard Kennedy School, Kim said.