The European Commission has already warned Italy that its higher-than-expected targets represent an unprecedented deviation from EU budget rules. At 1100 GMT it traded 0.1 percent up on the day at $1.1464.Italy is the third-largest economy of the 19-country euro zone, and a crisis there could unsettle the entire bloc.
"As long as I'm head of this movement and a minister of this government I'll always guarantee that Italy remains within the euro and in Europe", he added.
On Wednesday Conte said he saw no room for changing tack and on Thursday described the budget as "beautiful".
Concerns over Rome's expansive budget plans have weighed heavily on Italian government bonds in recent weeks, with the spread between German and Italian benchmark 10-year paper hitting 5-1/2 year highs on Friday.
"The economic plans of the government, while supportive of growth in the near term, do not amount to a coherent programme of reforms that will lift Italy's mediocre growth performance on a sustained basis", it said.More news: Saudi prince likely to survive worst crisis yet
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"We fully intend to press ahead with the government but if they continue to see conspiracies at every turn we're not there", Giorgetti said.
Euro commissioner Pierre Moscovici was in Rome on Thursday to hand a letter raising concerns over the draft budget to Italian finance minister Giovanni Tria. He insisted the increase in the structural deficit is less than the European Union calculates.
Italy's budget proposal is considered out of line with commitments made earlier, with a proposed deficit of 2.4 per cent. He said the main concerns revolve around the higher deficit, Italy's debt load and the possibility for growth.
"A harsh rebuke and the threat of further measures would likely boost the popularity of the populist coalition government", giving Italy's governing parties "an invaluable narrative to use during the campaign for the European elections in May", Piccoli said. He told a late-night talk show that the draft budget presented to President Sergio Mattarella's office contained a proposal to extend a tax amnesty on money held overseas and brought back to Italy.
Asked by reporters about a possible coalition rift, Prime Minister Giuseppe Conte - who is not from any political party - replied: "There is no division".
The 5-Star has opposed tax amnesties in the past but they are popular with the League's voter base, which traditionally comprises self-employed businessmen.
Italy's planned government spending growth of 2.7% is about 2.6% higher than the maximum allowed under European Union rules, which cap this at 0.1%, and allows the European Union executive to accuse Italy of non-compliance with the budgetary policy obligations, even as it tried to continue constructive dialogue with Italy to reach a final assessment.