Poland is sending their PT-91 tanks to Ukraine, or rather, has already sent them. Currently, there are at least 31 PT-91 tanks in Ukraine, but there is a possibility of more being sent.

TASS/. The Ukrainian military is using Polish-made armored vehicles: Polish-supplied PT-91 Twardy tanks, Rosomak armored personnel carriers and Krab howitzers in the attack on the Kursk Region ...

WARSAW, February 24. /TASS/. Poland has already sent to Ukraine the first Leopard 2 tanks out of the 14 promised, Polish Deputy Prime Minister and National Defense Minister Mariusz B·aszczak said ...