The planned deal aims to “provide Poland with a credible defense capability to deter aggression in the region and ensure interoperability with U.S. forces," the Defense Security Cooperation Agency said.
"This proposed sale will support the foreign policy and national security of the United States by improving the security of a NATO ally which is an important force for political stability and economic progress in Europe," the DSCA said in a statement.
It added that the sale "is consistent with U.S. initiatives to provide key allies in the region with modern systems that will enhance interoperability with U.S. forces and increase security."
The F-35 Joint Strike Fighter aircraft, produced by American company Lockheed Martin, and related equipment and support are estimated to cost USD 6.5 billion, the agency said.
'Most important contract in the history of Polish armed forces'
Poland's Defence Minister Mariusz Błaszczak tweeted that the purchase of the F-35 jets would be "the most important contract in the history of the Polish armed forces."
He said: "The US Department of State has approved the sale of 32 state-of-the-art F-35 aircraft to Poland. We are waiting for Congress's approval and are starting price negotiations. The most important contract in the history of the Polish armed forces is getting closer."
The US ambassador to Poland, Georgette Mosbacher, hailed the planned deal as “another important step in Polish-US relations.”
“We are stronger together,” she tweeted.
Under US law, the deal has yet to be approved by Congress, public broadcaster Polish Radio’s IAR news agency reported.
Cutting-edge jets to replace Soviet-era aircraft
The announcement by the Defense Security Cooperation Agency came after the White House in June conducted a flyover of two F-35 aircraft for Polish President Andrzej Duda as he was meeting US leader Donald Trump in Washington.
Poland's Błaszczak in May said his country aimed to buy 32 cutting-edge F-35A fighter jets from the United States as part of the country’s multibillion military upgrade programme.
Earlier President Duda said in a media interview that Poland was in talks with the United States to buy modern F-35 fighter jets for its air force to replace aging Soviet-designed MiG-29 aircraft.
In February, Poland's government signed a deal to buy 20 HIMARS artillery rocket systems from America for USD 414 million as part of a military modernisation drive.
Poland in March last year signed what officials described as a historic deal to buy an American Patriot air defence system for USD 4.75 billion.
Meanwhile, the Polish president in October 2017 signed into law plans to steadily increase the country’s defence spending to 2.5 percent of GDP by 2030.
Source: IAR, dsca.mil