Vasily Piskarev said a parliamentary investigation had found evidence that Germany's publicly funded international broadcaster had urged Russians to attend an unauthorized protest this summer, according to the lower parliamentary house's web site.

Russia's parliament will ask its Foreign Ministry to consider revoking broadcaster Deutsche Welle's right to work in the country for allegedly breaking laws on political impartiality, a senior lawmaker said on Friday.

Deutsche Welle's supervisory board rejected any suggestion of bias or interference.

"After consulting with the director and making its own inquiries, the board has concluded that DW's reporting from Russia is irreproachable... (It) rejects any suggestion that DW interfered in the internal affairs of the Russian Federation," it said in a statement from Berlin.

Board chair Karl Juesten, a Catholic bishop, said DW expected Russian authorities to let all its correspondents in Russia "report freely and without limitation."

Piskarev said the parliamentary investigation would also look into whether coverage by Britain's BBC and the U.S.-funded Radio Liberty had breached Russian election law.

Moscow has previously used laws regulating media ownership to threaten foreign outlets with expulsion in tit-for-tat responses to measures taken by foreign governments against its own media, including broadcaster RT.