Far-right Deputy Prime Minister Matteo Salvini on Tuesday insisted Italy would stick to its budget despite the European Commission rejecting it for increasing the deficit, Italian media reported.

"This doesn't change anything, let the speculators be reassured, we're not going back," League head Salvini said in Bucharest.

"They're not attacking a government but a people. These are things that will anger Italians even more and then people complain that the popularity of the European Union is at its lowest," he told journalists.

The European Union's executive arm earlier Tuesday rejected Italy's proposed 2019 budget and asked for a new plan, a first in European Union history, according to a source..

Italy's government said it would stick to a deficit of 2.4 per cent of annual economic output next year, which would be triple the amount forecast by the previous government and approach the EU limit of 3.0 percent.

The proposed budget would also aggravate Italy's already huge debt mountain, at some 130 percent of gross domestic product (GDP), way above the EU's 60-per cent ceiling and second only to Greece's in Europe.

Italy now has three weeks to revise its budget, under EU rules.