ROME - A vessel operated by the charity Doctors without Borders (MSF) rescued nearly 600 migrants sailing on an overcrowded boat which was in distress off the island of Sicily on Saturday, the group said on Twitter.

"After three hours of operation, the 599 survivors, including women and children, are now safely aboard ... and being cared for by the medical team," MSF tweeted, saying its vessel the Geo Barents had been conducting training activities when it was called in to undertake the rescue.

The migrants will be disembarked in the southern port of Bari, as assigned by the Italian authorities, MSF said, adding it would take around 40 hours to reach the port.

Charities have criticised the Italian administration of Giorgia Meloni, which takes a tough stance against illegal immigration, saying it often assigns ports too far away from the areas where rescues take place.

More than 47,000 migrant landings have been recorded in Italy so far this year, up from around 18,000 in the same period of 2022, interior ministry data show.

(Reporting by Angelo Amante; Editing by David Holmes)