Italy faces an election by mid-April which could return media magnate Silvio Berlusconi to power after he blocked attempts to form an interim government.
President Giorgio Napolitano summoned the speakers of both houses of parliament this evening and is expected to dissolve parliament tomorrow. By law, he would then have to call an election within 70 days.
April 13th is seen as the most likely poll date, just two years after Romano Prodi narrowly beat Berlusconi in the last election.
"Here we go: to the polls," read the front cover of daily Il Giornale, owned by Mr Berlusconi's brother Paolo.
Italy plunged into crisis after Prime Minister Prodi was forced to quit last month by defections in his centre-left coalition.
Reluctant to send Italians back to the polls, Mr Napolitano asked the speaker of the Senate (upper house), Franco Marini, to see if he could muster enough support for a temporary government to reform the electoral system.
But Mr Berlusconi (71) sensing a return to the post of prime minister he has held twice before, demanded a snap election.
After four days of talks with political leaders, Marini told Napolitano on Monday he had failed to find a majority backing an interim administration.
Mr Berlusconi's centre right has had a consistent lead in surveys of voter intentions. Yesterday, after reiterating his "No" to Marini, he said he had a lead of 10-16 points over the centre left, which will be led to the polls by Rome's 52-year-old mayor Walter Veltroni.
Mr Veltroni had supported an interim government to change voting rules that were widely blamed for the fragility of Mr Prodi's government, Italy's 61st since World War Two.
He now faces an uphill fight against Italy's richest man, but refuses to be written off just yet.