Addressing the European Parliament in Brussels, von der Leyen said the European Union expects "the rest of the world to take a clear stance against Putin's war of choice."
She added that the bloc has sent a message to China calling for sanctions imposed on Russia by the EU to be respected, or at the least, not to be circumvented and undermined.
"As a permanent member of the UN Security Council, China has a special responsibility to uphold international peace and security," von der Leyen told EU lawmakers.
She warned that the "war that Russia has unleashed" is "not limited to Europe" and will define how violations of international law are treated in the future.
"China has to take a clear stance on that," she added.
Some context: Von der Leyen said Wednesday that the EU would be placing further sanctions on Russia, likely on gas and oil.
The announcement came a day after the EU revealed its plans to impose a fifth wave of sanctions on Russia, including an import ban on Russian coal.
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