Nawrocki described the United States as Poland's "greatest ally" and said Poland stands with its allies during what he called "a time of major resolutions in the region".
He also suggested the Iranian regime, which he accused of arming Russia in its war against Ukraine, was collapsing.
Kosiniak-Kamysz expressed his condolences directly to the victims' families, US Secretary of Defence Pete Hegseth and the American people.
President Donald Trump paid tribute to the fallen soldiers, though warned further American casualties were possible.
Since the start of the US-Israeli air campaign against Iran on Saturday, at least 201 people have been killed and 747 wounded, according to Iranian sources, who stress the figures are preliminary.
Among the dead is Supreme Leader Ayatollah Ali Khamenei, along with military personnel and civilians.
Iranian forces struck targets in Israel and Gulf states on Sunday
Trump praised the operation, dubbed "Epic Fury", calling it an "unprecedented success" and saying he sees several options for ending the conflict.
(ał)
Source: IAR, PAP