(Reuters) -- The two Greek parties supporting the government of technocrat Prime Minister Lucas Papademos expelled more than 40 deputies on Monday for failing to back an austerity bill needed to avoid the country's chaotic default.

The conservative New Democracy party said it had expelled 21 out of its total 83 deputies. The Socialist PASOK party expelled about 20 of its 153 lawmakers.

(Reporting by Harry Papachristou)