NATO fears that China may support Russia in the conflict with Ukraine, Alliance Secretary-General Jens Stoltenberg said, adding that alliance members will discuss Beijing's role in the Ukraine war in Brussels.

"China has provided Russia with political support, including by spreading blatant lies and misinformation," Stoltenberg said ahead of an urgent NATO summit on Thursday.

He said China has questioned the right of independent countries to choose their own path, and the alliance is concerned that China could provide "material support for a Russian invasion."

Stoltenberg warned that decisions made at tomorrow's summit would have "far-reaching consequences."