North Korea has sent an envoy to Beijing to brief Chinese officials on recent political developments amid a downturn in relations between the formerly close communist neighbors.

The Chinese Communist Party's International Department said on its website Wednesday that its head Song Tao held talks the day before with Ri Su Yong, chief of the ruling Workers Party of Korea's International Department.

It said Ri briefed Song about last month's Workers Party congress, North Korea's biggest political event in decades.

Observers of North Korean politics said there was less top-level personnel reshuffling at the congress than expected, pointing to the stability of young leader Kim Jong Un's powerbase.

China-North Korea ties have cooled significantly under Kim, largely due to his regime's aggressive pursuit of nuclear weapon and missile technology.