(see related stories on government, Berlusconi) Rome, August 5 - The majority of voters of Italy's two biggest political parties do not want Premier Enrico Letta's left-right government to fall, according to a poll released Monday. Letta's grand-coaltion executive, which was cobbled together in April to end two months of political deadlock after February's inconclusive general election, is considered in grave danger after the supreme court last week upheld a tax-fraud conviction against ex-premier Silvio Berlusconi. But 75% of voters of Letta's centre-left Democratic Party (PD) said they thought the fragile executive made of up tradition foes should continue in power, despite the internal differences it faces, according to a poll by the SWG agency. The figure was only slightly lower, 70%, for voters of Berlusconi's People of Freedom (PdL) party. Nevertheless, just over half, 51%, see the government in danger of collapsing in the near future after the decision by the supreme Court of Cassation. Almost a third, 30%, expect it to break down in the autumn, 11% next year and 10% see an immediately meltdown.