President Donald Trump announced the measures on Wednesday after plans for a fresh summit with Vladimir Putin collapsed, complaining that talks with his counterpart "don't go anywhere".

China -- a major Russian trading partner -- has said it takes a neutral stance on the war and has refrained from condemning Moscow's 2022 full-scale invasion of Ukraine.

Asked about the new US sanctions at a daily press conference in Beijing, foreign ministry spokesman Guo Jiakun said "China consistently opposes unilateral sanctions that have no basis in international law and are not authorised by the United Nations Security Council".

In response to another question about Trump's statement that Chinese President Xi Jinping could have a "big influence" on Putin in efforts to end the war, Guo said that "dialogue and negotiations are the only feasible way out of the Ukraine crisis".

At the same press conference, Guo criticised sanctions on Russia agreed Wednesday by the European Union whose targets included Chinese companies, saying Beijing was "strongly dissatisfied".

"China is neither the creator of the Ukraine crisis nor a party to it," he said.

"The European side is in no position to make irresponsible remarks about the normal exchanges and cooperation between Chinese and Russian enterprises."

Guo urged Brussels to "stop making an issue out of China", vowing that Beijing "will take all necessary measures to safeguard its legitimate rights and interests".