Former Czech Prime Minister Petr Necas says he won't cooperate with prosecutors investigating his one-time chief of staff, and mistress, who is suspected of bribery and ordering a military intelligence agency to spy on his estranged wife.

Necas admitted having an affair with Jana Nagyova after his government collapsed in June. He has since divorced and married Nagyova.

Necas said Thursday investigators are biased, calling the case "a political process." He said he believed the intelligence service was working within law and that he was ready to testify in court.

Necas' conservative party was punished by voters in last month's election, receiving record low 7.7 percent of the vote.