In a post on X on Sunday, Kosiniak-Kamysz, who also serves as a deputy prime minister, said the Pentagon was now carrying out a review of forces that would form the basis for further decisions.
Speaking at a press conference, he named the cities of Poznań and Wrocław as possible locations, describing them as sites "rated highly by the American side."
The update follows a positive response Kosiniak-Kamysz said he received in mid-June from Pentagon chief Pete Hegseth, after Warsaw wrote to Washington on May 29 expressing its readiness to host US forces on a permanent basis.
The reply indicated the Pentagon was open to the idea, he told reporters.
Asked for more detail, Kosiniak-Kamysz said the process was highly formalised, covering both the choice of site and how a base would be paid for.
"A large part of the cost will of course fall on the Polish side, and that is our most important task today," Kosiniak-Kamysz said.
"We are working on it to make sure the government secures funding for the American bases."
He added that Prime Minister Donald Tusk had discussed several options at a meeting of a governmental security committee, which "gave the go-ahead to arrange financing and build up deterrence capacity."
On locations, Kosiniak-Kamysz pointed to the western city of Poznań, already home to the US Army's V Corps forward command post, where he said capacity could be expanded, and Wrocław in the southwest, where the airport is being redeveloped.
He also mentioned a newly handed-over rail freight facility for US troops at Świętoszów in the southwestern Lower Silesia region.
Around 10,000 US troops are currently in Poland under a mix of rotational and permanent arrangements, though most serve on rotation.
Earlier in June, Deputy Defence Minister Stanisław Wziątek said any permanent base would "certainly" be in western Poland, pointing to the northwestern city of Szczecin as an attractive option because of how easily heavy equipment could be moved there via an additional transport link.
(ał/gs)
Source: PAP