ROME: More than 400 migrants have been rescued from a boat off Malta after an 11-hour operation, Doctors Without Borders (MSF) said Wednesday after its ship responded to a distress alert.

While heading to shelter in the Mediterranean due to bad weather, MSF's rescue ship the Geo Barents received the distress signal, the charity tweeted.

The Geo Barents finally reached the boat at 4:00 am Tuesday “after more than 10 hours of navigation in a stormy sea”, MSF said.

“Unfortunately, the weather did not allow our team to directly perform the rescue, which could have endangered the lives of the people and those of the MSF team,“ it said.

But by early afternoon, the Geo Barents was able to launch its speed boats to the vessel, MSF tweeted along with photos showing the deck of the blue and white boat packed with people wearing life jackets.

“After more than 11 hours of operation, the rescue is now over and a total of 440 people, including 8 women and 30 children, are now safely aboard GeoBarents and being cared for by the team,“ the charity tweeted.

The Geo Barents was detained by Italian authorities in February for allegedly breaking new government rules on life-saving missions in the Mediterranean.

The charity said it had been accused of failing to share information, including voyage data recorder information on the position and movement of the ship.

Prime Minister Giorgia Meloni, the leader of the far-right Brothers of Italy party, took office in October after promising to curb the number of migrants landing in Italy.

The new law obliges charity ships to only perform one rescue at a time.

Critics say it increases the risk of deaths in the central Mediterranean, which is the most perilous crossing in the world.

Italy's geographical position makes it a prime destination for asylum seekers crossing from North Africa to Europe, and Rome has long complained about the number of arrivals.

Charities only rescue a small percentage of those brought ashore, with most saved by coast guard or navy vessels.

But the Italian government accuses charity ships of acting as a pull factor and encouraging people traffickers. - AFP