Budget Commissioner Günther Oettinger | Tobias Schwarz/AFP via Getty Images EU hits back hard at Italy’s budget threat in migration row Country will pay a big price if it withholds payments, Commissioner Günther Oettinger says.

Günther Oettinger, the EU's budget chief, warned Italy on Friday of "heavy sanctions" if its populist government follows through on a threat not to pay into the bloc's coffers in a row over migration.

The Italian threat and Oettinger's strongly-worded rebuke of an EU member country mark a further escalation in an already bitter, yearslong dispute over migration within the European Union.

The latest battle centers on whether 150 migrants rescued in the Mediterranean should be allowed to disembark from an Italian coast guard ship, the Diciotti, docked in a Sicilian port for the last four days.

The government, made up of the far-right League and anti-establishment 5Star Movement, has declared the migrants — mainly from Eritrea, Syria and Bangladesh, according to Intersos, a humanitarian organization that has staff on board — should not be allowed onto Italian soil unless other EU members agree to take them in.

The Italian government appears split over the budget threat.

On Thursday, Deputy Prime Minister Luigi Di Maio, the 5Stars' leader, said his party is no longer willing to "give €20 billion" to the EU if it does not reach a decision on the redistribution of migrants. (An Italian official said the figure is actually €15 billion.)

European Budget Commissioner Oettinger hit back hard on Friday.

"If Italy would refuse to pay its contribution to the #EUbudget, it would be the first time in the history of the EU. This would result in late payment interests. And a breach of Treaty obligations leading to possible further heavy sanctions," he tweeted.

"#EU is a Community of law and values and all Member States must play by the rules. Each Member State is expected to fulfil its obligations and has a duty to cooperate. #Cooperation not threats is the European solution."

In his remarks, Di Maio tied his threat to a meeting of officials from 12 EU member countries to discuss migration in Brussels on Friday. That gathering ended without agreement — although the Commission insisted it was not a decision-making meeting.

The Commission had also said the meeting was meant to discuss general policy issues rather than the specific case of the ship in Sicily. Italy tried and failed to change that, raising tensions in the room, an EU diplomat said.

“At the meeting, the Italians wanted to discuss the Diciotti but the others told them this was not the purpose,” the diplomat said. The scale of the divisions in the room was so high that “they were meant to sign a common declaration, but even that wasn't possible.”

The Italian government appears split over the budget threat. Prime Minister Giuseppe Conte reacted angrily on Facebook to the outcome of the Brussels meeting, saying that “Italy will draw the consequences.” But Foreign Minister Enzo Moavero said at an event in Rimini that paying into the EU budget is a “legal duty.”

Interior Minister and League leader Matteo Salvini, meanwhile, kept up his hard-line rhetoric on migration. He said Thursday he wants to adopt a scheme inspired by Australian policies, under which migrants would be sent back before even being identified — a plan that would contravene international legislation including the 1951 U.N. convention on refugees.