May 26 (Reuters) - Ukrainian President Volodymyr Zelenskiy on Thursday complained about divisions inside the European Union over more sanctions against Russia and asked why some nations were being allowed to block the plan.

The EU is discussing a sixth round of punitive measures, including an embargo on Russian oil imports. Such a move requires unanimity but Hungary opposes the idea for now on the grounds its economy would suffer too much.

"How many more weeks will the European Union try to agree on a sixth package?" Zelenskiy said in a late night address, noting that Russia was receiving a billion euros a day from the 27-nation bloc for energy supplies.

"Of course I am grateful to those friends who are advocating new sanctions. But where do the people blocking this sixth package get their power from? Why are they allowed to hold such power?" he asked.

Berlin hopes talks on the new round of sanctions will be completed soon but it will not be a topic at a leaders' summit next week, a German official said on Wednesday.

Zelenskiy's comments mark the second day in a row that he has sharpened his criticism of the world's approach to the war.

"Pressure on Russia is literally a matter of saving lives. And every day of procrastination, weakness, various disputes or proposals to 'pacify' the aggressor at the expense of the victim merely means more Ukrainians being killed," he said.

On Wednesday he savaged suggestions that Kyiv make concessions to bring peace, saying the idea smacked of attempts to appease Nazi Germany in 1938.

He also reiterated complaints that the world had so far failed to totally isolate the Russian banking system and was not providing heavy weapons quickly enough.

Russia calls its actions in Ukraine a “special operation” that it says is not designed to occupy territory but to destroy its southern neighbour's military capabilities and capture what it regards as dangerous nationalists.