Mateusz Morawiecki was commenting on media reports that mobile phones of some members of Poland's opposition had been infected with the Pegasus spyware made by Israel's NSO Group.
Pegasus is spyware enabling access to mobile devices and allowing the extraction of passwords, files, photos, browsing history, contacts and identity data.
The known victims include Roman Giertych, a former education minister who has also represented Donald Tusk, the opposition leader, in his professional capacity as a lawyer, Maria Wrzosek, an independent prosecutor, who has voiced opposition to the Polish government's reforms of the judicial system and Krzysztof Brejza, the main opposition Civic Coalition's chief of staff.
Morawiecki told a Tuesday press conference that media reports regarding the use of Pegasus should be "corrected" as "we must not allow ourselves to be imposed upon by fake news."
He reiterated that "there is no evidence that such wiretapping took place."
In a statement to PAP last week, Stanislaw Zaryn, the director of the National Security Department, called the Associated Press and subsequent Polish media reports unfounded, and said that all surveillance operations in Poland were carried out in keeping with binding laws and regulations.
Tusk said at a press conference on Tuesday that the Civic Coalition would file a motion to set up a parliamentary investigative commission to probe the use of Pegasus against the opposition.
"This is the deepest democratic crisis since 1989," Tusk added. (PAP)