North Korea's Kim congratulates China's Xi

North Korea's official KCNA news agency says Kim Jong-un has congratulated China's Xi Jinping on his re-election as president.

North Korea's Kim Jong-un Source: AAP

North Korean leader Kim Jong-uhas offered his congratulations to China's Xi Jinping upon his re-election as president.

North Korean state media issued a statement on Sunday, in a rare direct message from Pyongyang to Beijing after ties nosedived.

Kim has yet to visit China since assuming power in late 2011, with North Korea upset by China's strong support for UN sanctions over Pyongyang's nuclear and missile tests and China angered by those repeated tests.

But China has been strongly supportive of recent efforts by both South Korea and the United States to improve ties with North Korea, which includes a planned meeting between Kim and US President Donald Trump.

In the message reported by the North's official KCNA news agency, Kim said he hopes China will make even greater achievements under Xi's leadership.

"Expressing belief that the bilateral relations would develop in the common interests of the peoples of the two countries, the message wished the Chinese president big success in his responsible work," KCNA cited Kim's message to Xi as saying.