Security on the Korean Peninsula will also be part of the discussions with China, Wi told reporters.

Lee has sought to engage North Korea diplomatically, but there has been little progress so far. He needs Chinese cooperation in pressuring the North’s Kim Jong Un to give up his nuclear weapons. Beijing is the dictator’s biggest supporter, economically and diplomatically, Russia aside.

“China is a very important cooperative partner in moving toward peace and unification on the Korean Peninsula,” Lee said on Sunday.

Earlier in the day Seoul’s military said Pyongyang fired ballistic missiles off its east coast. And on Monday the North’s state news agency said the country test-fired hypersonic missiles to assess deterrence capabilities following recent developments, a reference to the US’s capture of Venezuelan president Nicolas Maduro over the weekend.

It remains unclear how much Lee will be able to push China on North Korea. In September, Xi had pledged to strengthen Beijing’s “traditional friendship” with Pyongyang.

And Seoul and Beijing are not natural allies.

US troops have been stationed in South Korea for decades in case of an attack from the North, and last year the two sides agreed to cooperate on building nuclear-powered submarines. The announcement drew warnings from China.

There are other sore spots, such as China’s unofficial restrictions on South Korean music and dramas that have been in place for a decade. K-pop and K-dramas are either unavailable or difficult to access on Chinese media platforms.

While China has never acknowledged a ban on Korean artists, it’s believed to be a protest against South Korea’s decision to deploy a US anti-missile system in 2016, which China sees as a threat to its military operations in the region.

Persuading Beijing to lift these restrictions is said to be high on Lee’s agenda. China is a massive market for Korean entertainment, which is already a huge global success.

Lee would also be seeking to put a stop to China’s build-up of maritime structures in waters between the two countries. Beijing says the structures are fish-farming equipment, but they have sparked security concerns in Seoul.