It now stands just 1.6 points behind its coalition partner, the more left-leaning 5-Star Movement, whose support has slipped slightly since it took 32.7 per cent at the election.
European Council President Donald Tusk congratulated the newly appointed prime minister, saying the appointment "comes at a crucial time for Italy and the European Union".
The Frecce Tricolori air force aerobatic demonstration team flies Saturday over the monument to the unknown soldier during ceremonies in Rome, marking.
Yet migrant arrivals to Italy actually plunged in the past year under the center-left Democratic Party, which signed controversial deals with Libya to beef up coastal patrols and prevent migrants from setting out in smugglers' boats across the Mediterranean Sea.
However, with each man emphasizing different priorities, there are doubts if the new government, led by a political novice with 5-Star sympathies, Premier Giuseppe Conte, will last a full 5-year term.
Italian media reported that the lineup will face a vote of confidence on Monday or Tuesday in both houses of parliament, which it is nearly certain to win thanks to Five Star and the League's combined majority in parliament.
When visiting Pozzallo and after delivering his speech, Mr Salvini went inside the town's migrant centre to meet some of the 158 people that had landed there when they were rescued by a humanitarian boat on Friday.
Salvini, who wants to open a migrant detention and deportation centre in every Italian region, later tweeted: "Either Europe gives us a hand in making our country secure, or we will choose other methods".
Lega leader Matteo Salvini will become the deputy prime minister and minister of the interior, while M5S chief Luigi DiMaio will jointly be deputy prime minister and take over the economic development portfolio.
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The tweet, which blew up on social media, was captioned: "I still haven't booked any holidays". We have a great group of lads who want be courageous and give it everything they have got".
Israeli PM Benjamin Netanyahu Says Not Surprised By Iran's Enrichment Intentions
As for curbing Iran's global influence, the supreme leader stressed that " we will continue our support for oppressed nations ". In return, Iran received relief from sanctions, most of which were dropped in January 2016.
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The USGS Hawaiian Volcano Observatory says the explosion was associated with a Magnitude 5.5 quake . There is a possibility that some residents could have died in the disaster, officials said.
The initial failure of Conte to form a government had alarmed financial markets, which feared a quick return to the polls that risked being tantamount to a plebiscite on Italy's keeping the euro currency.
A joint statement by the anti-establishment Five Star Movement and the far-right League announced that political newcomer Giuseppe Conte - who had been seen as a controversial choice - was still slated to serve as prime minister.
The new government features 18 ministers, including five women.
Salvini has long wanted his new post, from where he will aim to stop "the business" of migration, cracking down on people smuggling networks and speed up expulsions of illegal immigrants.
The opposition Democratic Party warned that the new government would be "Right-wing, populist and risky".
The new government delighted leaders of an increasingly bolder far-right in European politics.
"Gotta stay strong or the bully boys will be after you", he warned.
European Commission President Jean-Claude Juncker told a conference Thursday that he loved Italy, but refused to accept the frequent pass-the-blame mantra by Italian politicians that Italy's ills are the fault of the EU.
His first attempt to assemble an M5S-League coalition government collapsed on Sunday.