Italy says thousands of migrants have been rescued  over the weekend in the Mediterranean off the coast of Libya amid a surge in the number of people crossing the sea.

The Italian coastguard and navy said on Sunday that some 4,800 migrants were saved over the weekend and 10 bodies were recovered in what is said to be the biggest rescue mission of its kind so far this year.

According to reports, about 10 Italian vessels, including four private boats and a French ship, took part in the rescue operation off Libya.

The private Migrant Offshore Aid Station (MOAS) said on its Twitter page that it had saved 369 migrants, mostly from Eritrea, only on Sunday.

More than 800 people died on April 19, when a single migrant boat capsized in the Mediterranean Sea, in what was described as the deadliest incident recorded in the Mediterranean by the Office of the UN High Commissioner for Refugees (UNHCR).

The boat was about 20 meters long and was reportedly carrying over 900 people.

This image grab made from a handout video released by the Italian Coast Guard (Guardia Costiera) shows an Italian coastguard taking part in a rescue operation in the Mediterranean Sea on May 2, 2015. (AFP)

In November 2014, Italy ended its full-scale coast guard operation known as Mare Nostrum and the EU replaced it with Operation Triton.

Mare Nostrum reportedly saved the lives of over 100,000 migrants in more than a year, with a monthly cost of about 9 million euros (10.27 million dollars).

The new scheme has a monthly budget about a third of the previous one, with its maritime patrols generally restricted to territorial waters of the bloc’s 28 member states.

According to figures released by the UNHCR, 31 percent of the last year's arrivals to Italy were Syrians while18 percent were from Eritrea.