This was stated by Deputy Foreign Minister Pawel Jablonski on March 27.
"This procedure is conducted in secret to be effective. I don't think we are going to give it all away. Certainly not in one shipment," the diplomat said.
Earlier, Polish President Andrzej Duda said that Ukraine would receive four fighter jets in the near future.
Four MiG-29 fighter jets, donated by Slovakia, are on their way to Ukraine.