Polish President Andrzej Duda slammed the leaders of France and Germany over their phone calls with Russian President Vladimir Putin, saying it was like having talks with Adolf Hitler during World War Two, according to the German mass-selling daily Bild.

German Chancellor Olaf Scholz and French President Macron have both held one-on-one phone calls with Putin since Russia launched a devastating invasion of Ukraine, with Macron in particular stirring Ukrainian ire by saying Russia must not be "humiliated" so as to preserve chances of a diplomatic solution.

Duda, in an interview with Bild first released on its YouTube channel late on Wednesday, said such discussions only legitimized an illegal war in Ukraine.

"Did anyone speak like this with Adolf Hitler during World War Two?" Duda said. "Did anyone say that Adolf Hitler must save face? That we should proceed in such a way that it is not humiliating for Adolf Hitler? I have not heard such voices."

The conflict in Ukraine, described by Moscow as a "special military operation" to stamp out perceived threats to its security, has flattened cities, killed thousands of civilians and forced over 7 million people to flee the country.

Ukraine and its Western allies say Russia is waging an unprovoked war to grab territory.

In a joint call with Putin on May 28, Scholz and Macron urged him to release the 2,500 Ukrainian fighters captured at Mariupol's Azovstal steel plant and to speak directly with Ukrainian President Volodymyr Zelenskyy, according to Macron's Elysee Palace.

Italy and Hungary have urged the European Union to call explicitly for a ceasefire in Ukraine and peace talks with Russia, putting themselves at odds with other member states like Poland determined to take a hard line with Moscow

Last month, Zelenskyy savaged suggestions by some in the West that Kyiv give up territory and make concessions to end the war, saying the idea smacked of attempts to appease Nazi Germany in 1938 in the run-up to World War Two.