The highest-level Chinese envoy to visit North Korea in two years arrived in the country’s capital on Friday to try to improve relations that have soured over Beijing’s tightening of sanctions and expressions of support for US President Donald Trump’s calls for more pressure on the North to abandon its nuclear weapons programme.

Song Tao’s official mission is to brief North Korean officials on the outcome of China’s ruling Communist Party congress held last month. He is visiting as President Xi Jinping’s special envoy, according to Chinese and North Korean state media, but no other details about his itinerary or whether he will meet with North Korean leader Kim Jong-un have been announced.

After arriving, Mr Song met with Choe Ryong-hae, a vice chairman of the ruling party and one of the most senior leaders after Mr Kim.

The visit is seen as an effort by Mr Xi to explore a new approach in relations and likely also reflects Mr Xi’s desire to head off further pressure from Washington.

China’s relations with North Korea have deteriorated under Mr Kim, who has ignored Beijing’s calls to end the North’s nuclear weapons and ballistic missile tests and return to disarmament talks.

North Korea staged its sixth nuclear test on 3 September, detonating what it said was a hydrogen bomb, and most recently launched a ballistic missile on 15 September, firing it over the Japanese island of Hokkaido into the Pacific Ocean.

China, North Korea’s largest trading partner, says its influence with Mr Kim’s government is often exaggerated by the US and others. Beijing is opposed to measures that could bring down Mr Kim’s regime and lead to a refugee crisis along its border, and while enforcing harsh new UN sanctions targeting North Korea’s sources of foreign currency it has called for steps to renew dialogue.

The visit comes as Joseph Yun, the US envoy for North Korea, met Friday with his South Korean counterpart, Lee Do-hoon, on the resort island of Jeju in South Korea.

“China, of course, has a big role to play on Northeast Asia security issues,” Mr Yun was quoted by South Korea’s Yonhap news agency as saying, adding that he hopes China “regards the denuclearisation as a critical goal. We do hope that special envoy will forward that goal.”

Mr Song’s visit to North Korea also comes as China and South Korea are repairing their relations that soured over Seoul’s deployment of a US anti-missile system.

South Korean President Moon Jae-in is to visit China next month for talks with Mr Xi.

Mr Song is the first ministerial-level Chinese official to visit North Korea since October 2015, when Politburo Standing Committee member Liu Yunshan delivered a letter to Mr Kim from Mr Xi expressing hopes for a strong relationship, although the respite in frosty ties proved short-lived. Vice foreign minister Liu Zhenmin visited Pyongyang in October last year.

Mr Song heads the Communist Party’s International Department.