Polish officials alleged that elements within Pakistan's government shared blame for the apparent killing of a Polish engineer.
Pakistan's diplomat in Poland firmly rejected the charge that some members of the government are sympathetic to Islamic extremists.
Polish authorities were not able to officially confirm the death of Piotr Stanczak, abducted Sept. 28, but they said a seven-minute video purporting to show his beheading appeared authentic.
Foreign Minister Radek Sikorski said Poland would issue arrest warrants for the culprits, though Poland has no extradition treaty with Pakistan. Justice Minister Andrzej Czuma said the kidnappers were members of a Taliban group.