A former executive in Italian Prime Minister Silvio Berlusconi's media empire who was unexpectedly appointed as a government minister last month resigned in the midst of an embezzlement trial on Monday.

The sudden departure of Aldo Brancher, named as "minister for federalism" in June, deals a fresh blow to Berlusconi whose centre-right government is facing crippling internal divisions that could put its future at risk.

"I am announcing my irrevocable decision to resign as government minister," Brancher told a Milan court.

Brancher's appointment as minister with responsibility for overseeing moves to give Italy's regions more autonomy in matters including tax, education and health services had been heavily criticised by the opposition.

He caused further outrage when he used his newly acquired status as minister to claim immunity from his embezzlement trial and was forced to retreat and drop the claim only days later.

Reuters