Russian Foreign Minister Sergei Lavrov held a meeting with his Chinese counterpart, Wang Yi, to discuss a wide range of topics, including relations with the U.S. and the Ukrainian conflict, the Russian foreign ministry said on Thursday.

Foreign ministers from the G20 top economies were to meet in South Africa on Thursday and Friday, amid tensions between members over the Ukraine war, trade disputes and with the top U.S. diplomat staying away owing to a feud with the hosts.

U.S. and Russian participants have quietly met in Switzerland for unofficial discussions about the Ukraine war in recent months, including as recently as last week, three sources with knowledge of the matter said.