A German Cabinet minister who tipped-off another senior politician of a probe involving a prominent lawmaker says he'll resign if prosecutors decide to investigate him.

Center-left lawmaker Sebastian Edathy resigned his seat last week, citing health reasons, days before police searched his home and offices.

The head of the Hannover prosecutors' office, Joerg Froehlich, said Friday the case centers on alleged ordering of pictures of underage boys, though it's not clear whether they legally constitute child porn. Edathy denies ordering or possessing child porn.

On Thursday, it emerged that Hans-Peter Friedrich, then Germany's interior minister, told the leader of Edathy's party in October that Edathy's name had come up in an investigation. Friedrich, now agriculture minister, said Friday he's convinced he acted correctly but will quit if prosecutors investigate him.