BERLIN, Feb 27 (Reuters) - Chancellor Angela Merkel's centre-left challenger in this year's German election has dismissed former Italian premier Silvio Berlusconi and comic-turned-politician Beppe Grillo as "clowns" following their strong performance in weekend elections.
Peer Steinbrueck, a former finance minister with a reputation for straight talk, said he was "appalled that two clowns have won" and made it clear he was referring to Grillo and to Berlusconi, calling the latter "clearly a clown with a testosterone boost".
"My impression is that two populists won," said Steinbrueck, a Social Democrat (SPD), at a regional political rally in Potsdam late on Tuesday.
Berlusconi is deeply unpopular in Germany and has been attacked repeatedly in the media.
But it was unclear whether Steinbrueck had done himself any favours with his frank talk. In Germany, politicians are expected to strike a serious tone and refrain from interfering in the internal affairs of European partners. On Twitter, some commentators dismissed Steinbrueck as the "real clown".
Italy's inconclusive elections, which threaten to tip the euro zone back into crisis, showed a surge in support for anti-establishment Grillo's 5-Star Movement and a surprisingly strong result for Berlusconi. He had been expected to lose heavily to the centre left, which won the lower house but not the Senate.
Both Grillo and Berlusconi campaigned against the austerity measures implemented by technocrat Prime Minister Mario Monti at the urging of Germany's conservative chancellor Merkel.
Grillo, in his popular blog, laid into Merkel for imposing Germany-style fiscal austerity on Italy while Berlusconi has made more personal attacks on Merkel, whom he blames for his fall from power in 2011 because of her hesitance on bailouts.
Berlusconi, who has been sentenced for tax fraud and is on trial accused of having sex with an under-aged prostitute, is reported to have made rude remarks about Merkel's appearance in a phone call wiretapped by investigators, though he denies this.
Merkel is more diplomatic than the bombastic Steinbrueck, a former German finance minister whose campaign for the election in September has got off to a poor start.
Merkel's parliamentary allies and even cabinet ministers had voiced concern about the possibility of a Berlusconi comeback before Sunday and Monday's elections but the chancellor kept any reservations to herself.
Steinbrueck made waves with undiplomatic statements when he served as finance minister under Merkel between 2005 and 2009, referring to the Swiss as Indians running scared from the cavalry during a crackdown he led on tax havens. (Reporting by Stephen Brown; Editing by Noah Barkin)