Lee is the first South Korean leader to visit Beijing in six years and his meeting with Xi comes a day after the nuclear-armed North fired two ballistic missiles into the Sea of Japan.

The pair will meet for an opening ceremony and a summit before the signing of an agreement and a state banquet, Seoul has said.

The South Korean leader, accompanied by a delegation of business and tech leaders, hopes to secure pledges to expand economic cooperation with his country's largest trading partner.

He has called for South Korea and China to work towards "more horizontal and mutually beneficial" trade.

On Monday Lee met with top executives from both South Korean and Chinese firms at Beijing's opulent Diaoyutai State Guesthouse, Seoul's Yonhap news agency reported.

South Korea and China "have helped each other grow through interconnected industrial supply chains and led the global economy", he told them.

Among the Chinese firms represented were battery giant CATL as well as phone maker ZTE and tech giant Tencent, Yonhap said.

On the South Korean side, Lee is accompanied by Samsung Electronics chairman Lee Jae-yong and Hyundai Motor Group's executive chair Chung Eui-sun, among others.

Lee also hopes to possibly harness China's clout over North Korea to support his bid to improve ties with Pyongyang.

"China is a very important cooperative partner in moving toward peace and unification on the Korean Peninsula," Lee said during a meeting with Korean residents in Beijing on Sunday, according to Yonhap.

- Pyongyang tensions -

Hours before Xi and Lee were due to meet, Pyongyang declared that it had launched two hypersonic missiles and that its nuclear forces were ready for "actual war".

Xi and Lee last met in November on the sidelines of the APEC summit in the South Korean city of Gyeongju -- a meeting Seoul framed as a reset of ties after years of tension.

Seoul has for decades trodden a fine line between China, its top trading partner, and the United States, its chief defence guarantor.

And Lee's trip comes less than a week after China carried out massive military drills around Taiwan, the self-ruled island it claims as part of its territory.

The exercise, featuring missiles, fighter jets, navy ships and coastguard vessels, drew a chorus of international condemnation that Seoul has notably declined to join.

Lee also deftly stayed on the sidelines since a nasty spat erupted between Beijing and Tokyo late last year, triggered by Prime Minister Sanae Takaichi's suggestion that Japan could intervene militarily if China attacks Taiwan.

In an interview with Chinese state broadcaster CCTV on Friday, Lee said he "clearly affirms" that "respecting the 'one-China' principle and maintaining peace and stability in Northeast Asia, including in the Taiwan Strait, are very important".

bur-oho/je/mtp

CATL

ZTE

Tencent

Samsung Electronics