Slovakia must make a decision on sending MiG-29 fighter jets to Ukraine, Defence Minister Jaroslav Nad said on Thursday, referring to a fleet of 11 that were retired last summer, not all of them in operational condition.

"I think it is time to make a decision," Nad said on Facebook. "People are dying in Ukraine, we can really help them, there is no room for Slovak politicking."

Nad said he had spoken to Poland's defence minister at a European Union meeting on Wednesday and was told Warsaw would agree to a joint process to hand over MiG-29 jets to Ukraine.

Western countries that have provided Ukraine with arms have so far declined to send fighter jets. Poland has said it would be willing to send war planes in a coalition of countries.

On Thursday, the head of the president's office, Pawel Szrot, told Radio Puls the number of aircraft would be less than the 14 German-made Leopard 2 tanks Poland has promised to deliver to Ukraine.

"It will certainly not correspond to the number of Leopards transferred. We will certainly do it in a broader international coalition," Szrot said.

Countries along the NATO military alliance's eastern flank, like Poland and Slovakia, have been strong backers of Ukraine since Russia invaded Ukraine last year.

Warsaw's commitment to its neighbour has been important in persuading European allies to donate heavy weapons to Ukraine, including tanks, a move opposed by several governments, including Germany, until recently.

Slovak Prime Minister Eduard Heger said last month the country could start discussions on delivering planes after Kyiv officially asked for them.

Heger's government is ruling in a caretaker capacity until early elections set for September, and Nad has said he was prepared to involve parliament in deciding on the jets plan. (Reporting by Jason Hovet in Prague and Pawel Florkiewicz in Warsaw; Editing by Jan Lopatka, Angus MacSwan and Nick Macfie)