Duda was speaking alongside NATO chief Jens Stoltenberg during a visit to Poland's Lask airbase.

"We are not sending our planes because that would mean military interference in the conflict," Duda said when asked if Poland would send planes as well as the arms and ammunition it has already dispatched.

"NATO is not a party to this conflict," he said.

The Western military alliance has for the first time deployed part of its response force to Eastern Europe to respond to mounting concern over Russia's invasion of Ukraine in the formerly Moscow-dominated region.

During his visit on Tuesday, Stoltenberg said that NATO "is not going to send troops into Ukraine or move planes into Ukrainian airspace".