Poland will send Ukraine four MiG-29 fighter jets in coming days, President Andrzej Duda said on Thursday, making it the first of Kyiv’s allies to provide such aircraft.

One of Ukraine’s staunchest supporters, Warsaw, has taken a leading role in persuading sometimes hesitant allies to provide Kyiv with heavy weaponry. It has said that any transfer of jets would be as part of a coalition.

“Firstly, literally within the next few days, we will hand over, as far as I remember, four aircraft to Ukraine in full working order,” Andrzej Duda told a news conference. “The rest are being prepared, serviced,” he added.

On Tuesday, Polish Prime Minister Mateusz Morawiecki said that deliveries could be made in four to six weeks.

Duda said that Poland had roughly 10-20 MiG 29 jets in total.

Earlier, Warsaw sent 14 German-made Leopard 2 tanks to Ukraine.