If Italy does not pay its budget contributions on time, it will face interest payments, European Union Commissioner Guenther Oettinger warned on August 29.

Last week, Italy’s Deputy Prime Minister Luigi Di Maio threatened to withhold next year’s EU contributions if partners did not agree to take in rescued immigrants who were being held on a ship in an Italian port.

And then when only Ireland and Albania offered to help with the migrants, Di Maio said Italy would veto the EU’s seven-year budget plan if the bloc does not start to share the burden of seaborne migrant arrivals.

“One can only warn Rome not to entwine questions on migrant policy with the EU budget,” Oettinger, a German who serves as the bloc’s budget commissioner, told Die Welt daily.

“All European members are obliged to pay their contributions on time. Anything else would be a breach of the treaty which would trigger interest payments,” he told the paper.

As reported by the Reuters news agency, Italy’s annual contribution to the EU budget is around €14bn. Asked about Oettinger’s remarks during a visit to Cairo, Di Maio said Italy’s position on vetoing the budget was unchanged.

“If in the coming days [EU partners] want to rediscover the spirit of solidarity on which the European Union was founded, maybe we can talk” about lifting the veto, he said.

Di Maio is the leader of the anti-establishment 5-Star Movement, which took power in June in coalition with the far-right League party. The new government has promised to make immigration one of its priorities.