ROME — Italy's aviation authority has barred humanitarian migrant rescue groups from using a Sicilian airport to launch search and rescue flights over the Mediterranean, in the government's latest crackdown on their activities.

An ordinance from ENAC's western Sicilian office said the flights interfered with the Italian coast guard's exclusive role in coordinating search and rescue efforts and put migrant lives at risk. Non-governmental rescue groups that continue using the Lampedusa, Sicily airport risk unspecified fines and the aircraft may be seized, it said.

The ordinance marked a new effort by the government of Italian Premier Giorgia Meloni to crack down on migration from North Africa, a key campaign promise that brought her right-wing coalition to power in 2022.

The German rescue group Sea-Watch, which operates its Seabird aircraft to spot migrant boats in distress, vowed to continue its flights. It said late Tuesday that the flights were the only independent way ''to document the daily violations of human rights that occur'' in the Mediterranean.

It cited the activities of the Libyan coast guard, which is trained and equipped by the European Union. Libyan rescue ships regularly intercept migrant smuggling boats and bring them back to shore in Libya, where the United Nations and human rights groups have documented grave abuses at migrant holding facilities.

''This attack that tramples on international law will not stop us from continuing to annoy those who would like what happens daily in the Mediterranean to remain a secret,'' Sea-Watch said in a social media post.

In addition to targeting smugglers and the migrants themselves, the government has taken a series of measures to complicate the work of humanitarian aid groups that rescue migrants at sea. The government accuses these groups of encouraging risky departures by their presence in the Mediterranean and fuelling the trafficking demand.

The aid groups say they are saving lives in the absence of an adequate European response to the migration problem and have lashed out at the Italian measures, which they say are designed to limit their time at sea.

In addition to occasional law enforcement sequesters of ships and investigations, Italy now assigns rescue ships to ports far from the active search zone and requires them to return to port after each rescue, rather than stay at sea to pick up as many migrants as possible.

It wasn't immediately clear what the groups would do to keep flying, and whether they could find alternative airports close enough to the search zone.

Lampedusa, which is closer to Africa than the Italian mainland, has long been the destination of choice for migrant smugglers who charge people hundreds of euros apiece to be crammed into overcrowded boats to make the dangerous crossing from North Africa.

Meloni has vowed to strangle the flow, and has inked a series of agreements to incentivize North African countries to prevent departures, while also persuading would-be EU member Albania to build two centers to process the asylum claims of those migrants who are rescued by Italian ships.

To date, the number of migrants arriving in Italy is way down this year compared to the same period last year: 17,666 had arrived as of Wednesday, compared to 44,739 by this time last year and slightly more than the 11,797 in 2022, according to interior ministry data.