ROME, Oct 23 (Reuters) Italy's centre-left premier, Romano Prodi, edged closer to a government collapse once more today when a minister being probed in an embezzlement case threatened to resign if the cabinet did not support him.
Justice Minister Clemente Mastella has often threatened to quit the 17-month-old government, stripping it of its wafer-thin majority, because he and his small Udeur party have more conservative, Catholic ideas than most of the ruling coalition.
The Udeur demanded ''a definitive political clarification'' of whether Mastella still had cabinet support, ''otherwise it will no longer be possible to keep the current coalition alive''.
Prodi, strolling with his wife when a horde of reporters asked if he was worried, said he was ''very calm.'' But if Mastella left the cabinet and the alliance, Prodi would lose his majority in the Senate, where Mastella and his party have three seats.
Prodi already relies on unelected lifetime senators to get laws through the Senate. The opposition's Silvio Berlusconi is again predicting, as he did a year ago, that the budget vote at year-end will finish Prodi's rule.
Mastella has come under attack for using an official plane to attend a sporting event at which he handed out third prize. He complained he was being made the victim of a vitriolic campaign of disenchantment with all Italian politicians.
A more serious allegation is that Mastella used his position as justice minister to seek the transfer of a magistrate in the south of Italy investigating Mastella and Prodi's alleged links to businesses accused of embezzling European Union funds.
He and Prodi deny any wrongdoing.
Drama was added to the case last week when the magistrate was sent an anomymous letter containing a bullet -- similar to a threat sent to Prodi with a demand that he step down.
As usual with the bickering coalition, the fiercest attack on Mastella came from within. Infrastructure Minister Antonio Di Pietro urged Prodi to get rid of Mastella for what he called interests ''incompatible'' with his position.
Mastella shot back that Di Pietro, a former anti-corruption magistrate, was ''illiterate regarding the law''.
The hard left, marginalised in the coalition by the merger this month of two centrist allies into the new Democratic Party, enjoyed the spectacle. ''I suggest bringing in the UN blue helmets,'' said Communist leader Oliviero Diliberto.
Conservative former premier Berlusconi is quoted as saying he will bring down Prodi and prepare for elections next March.
Prodi still has 3-1/2 years to serve but Italian premiers rarely last the full term and Prodi resigned briefly this year to bring the coalition to heel. He has dropped behind Berlusconi's centre-right in opinion polls.
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