Silvio Berlusconi, Italy’s centre-right prime minister, aims to deliver a knock-out punch on Tuesday night when he confronts Romano Prodi, his centre-left challenger, in the first of two televised election debates.

“Invite an undecided voter to dinner!” the website of Mr Berlusconi’s Forza Italia party urged supporters on Monday, confident in the belief that the premier will vanquish his opponent in face-to-face combat.