Updated at 5.08pm - Added Metsola, Agius comments

Italy’s deputy Prime Minister has cranked the country’s sabre-rattling against Malta up a notch, linking tensions over sea rescues of migrants to Sicily allowing electricity to Malta through the interconnector.

“We give Malta electricity, there is a cable that starts in Ragusa that gives Malta electricity, and Malta refused to help out the Aquarius, which was in its SAR [Search and Rescue] zone,” Luigi di Maio said on Italian national television. He was being interviewed on Rai Uno show Porta a Porta.

Malta buys electricity from European markets at market prices, with the country linked to the EU grid network through the cable Mr Di Maio alluded to.

Italy has locked horns with Malta in recent weeks over its maritime policy for sea rescues. Italy’s populist coalition government believes Malta is not playing its part in taking in migrants rescued at sea, and argues that it has been left alone to manage the crisis.

On its part, the Maltese government notes that Malta takes in more asylum applications than Italy on a per capita basis and that it abides by international maritime law, which, by its interpretation, requires the country to provide succour to vessels in distress when Malta is the closest safe harbour. 

Tensions between the two countries came to a head when the Italian government opted to close its ports to the MV Aquarius and its 627 rescued migrants, announcing the decision when the ship was already en route to Italy.

“I’m convinced that a few ‘nos’ to Europe will lead to several ‘yeses’ for Italy,” Mr Di Maio added on Porta a Porta.

Mr Di Maio’s tough talk comes just days after his cabinet and party colleague, Infrastructure Minister Danilo Toninelli, said that if Malta could not cope with its vast search and rescue zone it should hand over part of it "and the money they receive for it" to Italy.

That inflammatory comment drew a sharp reaction from the Maltese government, which said Mr Toninelli was either misinformed or out to stir a “useless controversy”, adding that Malta received no money for its search and rescue zone.

In a separate incident, M5S MPs stormed out of an assembly in Sicily just as President Marie-Louise Coleiro Preca began addressing them. The incident prompted an embarrassed apology from the head of the assembly.

Peter Agius, who in his professional life serves as one of the spokesmen for European Parliament president Antonio Tajani, was the first to react to Mr Di Maio's inflammatory statement. 

"Malta pays for its electricity, it's no gift!" he wrote on his personal Facebook page. "I hope the European Council on June 28 comes up with a solution and that these TV politics are brought to an end." 

Labour Party MEP candidate and adviser to the Prime Minister Cyrus Engerer pounced on the statement and related it to domestic politics, citing it as evidence that the government was right to invest in an LNG-fired power station.

“This confirms how important... it was to not rely solely on the interconnector,” Mr Engerer wrote on Facebook.

MEP Roberta Metsola was also unimpressed by the Italian deputy Prime Minister's words. 

"Malta buys electricity, Mr Di Maio does not "give" it to us or to anyone," she tweeted. "Selling is not giving."

Government "surprised" by statement

The Maltese government expressed its "surprise" at di Maio's statement, making it clear that Malta bought its energy at commercial rates from various European providers on the European grid.

The agreement on the interconnector supply is governed by European rules and specifies minimum and maximum loads, and circumstances as to when such loads can be reduced, it said.

"The Maltese government is confident that the competent Italian authorities will draw the Italian Deputy Prime Minister’s attention to this fact and that the said agreement is governed by rule of law," it said pointedly.

The Maltese government also drew attention to the fact that with its latest investment in its own power plants, Malta is self-reliant for its energy requirements. The interconnector is used as part of an energy mix as part of its energy policy.