Polish Deputy Prime Minister and Defence Minister Władysław Kosiniak-Kamysz signed the contract at a ceremony in Warsaw.
The missiles, called AIM-120 AMRAAM (Advanced Medium-Range Air-to-Air Missiles), are due to be delivered in their state-of-the-art AIM-120D3 version between 2030 and 2031, as part of the country's effort to modernise its army.
They will be used by Poland's fleet of 32 F-35 multirole stealth fighters, the first 11 of which are expected to arrive next year.
"The planes must be well equipped and that is why we're signing this deal today, for the most advanced version of these missiles," Kosiniak-Kamysz told reporters.
He added that Poland was "a tried and tested ally of the United States, and we aim to strengthen this cooperation."
Kosiniak-Kamysz said the purchase of the AIM-120D missiles, the F-35 multirole fighters and the modernisation of the F-16 fighter jets all represented "an investment in the security of our airspace."
The AIM-120D guided missiles are medium-range air-to-air missiles capable of hitting targets up to 180 kilometres away. They constitute standard equipment for US and NATO fleets, including the F-35 multirole stealth fighters, according to officials.
The Dutch F-35s which took part in combating Russian drones that violated Polish airspace in September, were equipped with AIM-120D missiles, reporters were told.
The AIM-120D3 missiles that Poland is buying are the most modern version manufactured by US defence contractor Raytheon in Tucson, Arizona since August 2022, Polish state news agency PAP reported.
Poland's F-16 fighter jets are equipped with the earlier "C" version of the AMRAAM missiles, according to the wp.pl news website.
The fleet of F-35 multirole stealth fighters, which is set to number 32 planes delivered from 2026 onwards, will now be equipped with AIM-120D missiles, delivered between 2030 and 2031, officials told reporters.
The US Department of State in April approved the sale to Poland of 400 AIM-120D3 Advanced Medium Range Air-to-Air Missiles, along with associated equipment and logistics support, for an estimated cost of USD 1.33 billion, according to an announcement at the time by the Pentagon's Defense Security Cooperation Agency.
According to the US State Department, Poland has requested to buy 400 AIM-120D3 missiles, 16 AIM-120D3 AMRAAM guidance sections, and one AIM-120 AMRAAM Instrumented Test Vehicle.
(pm/gs)
Source: PAP, wp.pl, X.com