The Belgian government is bloodied and bruised — and it's Theo Francken who threw the punches.

Until Sunday, Francken was part of the government, as state secretary for asylum and migration. But now his party, the New Flemish Alliance (N-VA), has left executive power over a controversial international migration pact that they refused to support. That leaves Prime Minister Charles Michel leading a minority government that could fall at any time.

The split was a long time coming, in large part because of Francken, whose blunt style and uncontrolled tweeting turned the 40-year-old into Belgium's most popular politician, according to several surveys, but who also startled his coalition partners with his unexpected flare-ups and his tough take on tackling the migration crises.

"There is huge concern and even anger and frustration among a big part of the population about the chaotic organization of asylum and chaotic migration flows into Europe ... The illegal chaos has to end," Francken told POLITICO in an interview at his party's headquarters in Belgium's federal parliament, where the former junior minister is setting up a new, makeshift office.

The N-VA went from being a renegade force with a separatist agenda to being a broad right-wing party.

A hardline stance on migration is what made Francken an N-VA star, and it is why Michel's four-party coalition reached breaking point Sunday, with the Flemish nationalists strongly objecting to the prime minister's planned support for the Global Compact for Safe, Orderly and Regular Migration (which was backed by more than 150 countries — including Belgium — at a United Nations conference in Marrakesh, Morocco, on Monday).

Less than 48 hours after leaving government, the N-VA was in campaign mode ahead of federal, regional and European elections in May, hammering Michel for being weak on migration.

"That Marrakesh pact was not acceptable," Francken said. "It touches on the core of the issue: handing over sovereignty and the right to self-determination, and the preservation of autonomy on one's borders. We handed over way too much and that needs to end."

"That's the DNA of our party, in our fight for Flemish nation building but also in keeping control of our own borders," he added.

Rise and rise of the N-VA

Leaving the government it shaped and dominated for four years is the latest twist for the Flemish nationalists.

The N-VA went from being a renegade force with a separatist agenda to being a broad right-wing party able to work with the country's mainstream forces while pushing strict law and order rules and budgetary discipline.

While party leader Bart De Wever didn't join the federal government (he's mayor of Antwerp), Jan Jambon as interior minister gained an international reputation for his handling of the terrorist attacks in Brussels and Paris. As he left office with the rest of the N-VA on Sunday, Jambon was praised even by the coalition partners he was leaving behind.

Not so with Francken.

Popular with De Wever, Jambon and other party bigwigs, Francken also caused trouble, whether by saying he would "clean up" a park where asylum seekers has camped out, by accusing the NGO Doctors Without Borders of being involved in people smuggling, or with political slips-of-the-tongue that had diplomatic fallout.

One example was when Carles Puigdemont was fleeing prosecution from Spanish authorities. It was Francken who said the ousted Catalan president could seek asylum in Belgium — jeopardizing his own government's relations with Madrid. Spanish Foreign Minister Josep Borrell on Monday described the departure of the Flemish nationalists from government as "good news."

Francken "is a central player, but he has critics within the party too," said Carl Devos, a political analyst and professor at Ghent University. "Some think he is helping attract right-wing voters, but others think he causes problems."

EU efforts to distribute migrants around the bloc also get short shrift from Francken.

Now that the messy business of government is out of the way, the N-VA will be hoping Francken can win over voters who drifted to the far-right Flemish Interest party in last October's local election.

"The N-VA previously got praise for defeating Flemish Interest. However, the election in October was a comeback for Flemish Interest, and a loss for N-VA," said Devos. "Some within the party feel the right flank wasn't properly covered."

Right side of politics

"My country will be on the right side of history," Michel said at the U.N. gathering in Morocco, defying right-wing leaders across Europe who refused to back the migration pact.

Opponents to the pact include Austrian Chancellor Sebastian Kurz, Italian Interior Minister Matteo Salvini and the Hungarian and Polish governments.

"Theo Francken is perfectly integrated in this niche," said Ico Maly, a researcher at Tilburg University who specializes in the N-VA and the impact of social media on politics.

Francken said he understands Salvini's politics and the Italian's plans to change Italy's asylum policy have "a lot of things in it that we're already doing."

The Belgian also wants the Geneva Convention on human rights to be altered to allow for a "pushback" policy under which boats containing migrants could be turned away from Europe.

"Pushbacks no longer are a controversial item," he said. "I believe I was the intellectual trailblazer to plead for this in a moderate and humane way." The idea was condemned by the European Court of Human Rights in 2012.

EU efforts to distribute migrants around the bloc also get short shrift from Francken. "If you don't close your borders, it is not possible," Francken said. "You can't get it agreed with Eastern Europe. And Eastern Europe is only getting stronger."

Those kinds of views will be on full display in the coming months as Francken seeks to drum up support for the N-VA, especially if Michel fails to hold his fragile coalition together.

"Theo Francken speaks for the N-VA's part of the electorate that leans towards Flemish Interest," said Maly. "The party needs more than that group to keep its position — but they can't do without it either."

Simon Van Dorpe and Jacopo Barigazzi contributed reporting.