The media magnate refused to answer when state TV journalist Lucia Annunziata asked about his business affairs and the Iraq conflict.

"You can't tell me what to do," he said as the conversation descended into bickering and he accused her of bias.

"This is my show, I'll decide the questions," Ms Annunziata retorted.

link to video- watch the incident

She told him he was "not used to taking journalists' questions".

The prime minister faces his first TV debate with opposition leader Romano Prodi on Tuesday as the race hots up for the 9-10 April election and his coalition lags behind in opinion polls by several points.

'War machine'

Mr Berlusconi effectively owns three private TV stations in Italy while his supporters run two of the three Rai, or state, TV channels.

Only Rai Tre, the least watched of the three, is critical of the prime minister and he was being interviewed on its In A Half-hour programme.

After just 20 minutes, he was gathering up his papers and telling Ms Annunziata her programme was "a war machine set against the prime minister".

The interviewer had asked him why he was only known abroad for his support for US President George W Bush in Iraq, as well as possible conflicts of commercial and political interest.

Accusing her of "prejudices" and being "on the left", he said: "You should be a little bit ashamed."

As he left the studio, his microphone was still attached and he could be heard shouting: "And they say I'm the one who controls Rai!"

Rai Tre showed the interview uncut on Sunday afternoon.

Correspondents note that it is rare for Italian interviewers to take a confrontational approach with politicians.

While Mr Berlusconi dominated TV screens earlier in the year, strict campaigning laws have since taken effect, forcing the media to give equal space to Italy's many political parties and thereby reducing his exposure.