The EU delegation will not support the statement at the meeting of foreign ministers of the "Group of Twenty" (G20) in India, if it does not contain a condemnation of Russia's war against Ukraine.
This was reported by the Reuters agency with reference to its own source.
Separately, the head of the foreign policy department of the European Union, Josep Borrell, said that the success of the meeting in New Delhi will be measured by what it can do about the war in Ukraine and its consequences.
"This war should be condemned. I hope, I am sure, that India's diplomatic potential will be used to make Russia understand that this war must end," Borrell told reporters.
Russia said it was using the meeting to tell the world who it believed was responsible for the political and economic crisis in which the world found itself.
The main G20 meetings will take place on Thursday after a welcome dinner on Wednesday.
The G20 includes the wealthy G7, as well as Russia, China, India, Brazil, Australia and Saudi Arabia, among others.
India, as the host, said the war in Ukraine would be an important topic of discussion, but "issues related to food, energy and fertilizer security, the impact of the conflict on the economic challenges we face" would also receive "due consideration attention".
The foreign ministers' meeting comes days after the G20 finance ministers' meeting in Bengaluru failed to reach a consensus on a joint statement.
The reason was the reluctance of Russia and China to agree on formulations acceptable to others regarding the Russian Federation's war against Ukraine.