Malta private rescue mission aids migrants

About 250 migrants have been saved in Europe's first private migrant rescue mission, the organisation behind the operation says.

The group of migrants, mainly made up of Syrians and Palestinians, included 40 children, said the Migrant Offshore Aid Station (MOAS), which was launched officially on Monday from Malta.

Italian authorities directed the private organisation's vessel, the Phoenix, to step in after the migrants were spotted in trouble on board a wooden fishing boat south of Malta.

The migrants were taken on board, awaiting an Italian military vessel to pick them up.

The conditions of those on board is not yet known.

The non-governmental organisation is the brainchild of entrepreneurs Chris and Regina Catrambone.

They were inspired by an appeal made by Pope Francis to dedicate more than 4 million euros ($A6.00 million) of their own money to set up the venture.

The aim of the operation is not to ferry rescued migrants, but for the vessel to act as a station at sea to help identify vessels at risk and give first assistance in co-ordination with military forces in Malta and Italy.

"We will not save everybody, but if we save one person from drowning, it's a success," Regina Catrambone said during the launch.