Rescued migrants stand in an Italian Coast Guard vessel after transferring from the Migrant Offshore Aid Station (MOAS) ship MV Phoenix between Libya and the Italian island of Lampedusa, August 3, 2015 (Reuters)

Rescued migrants stand in an Italian Coast Guard vessel after transferring from the Migrant Offshore Aid Station (MOAS) ship MV Phoenix between Libya and the Italian island of Lampedusa, August 3, 2015 (Reuters)

Migrants are helped to cross from their rubber dinghy to a Migrant Offshore Aid Station (MOAS) RHIB (Rigid-hulled inflatable boat) before being taken to the MOAS ship MV Phoenix, some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)

Migrants on a rubber dinghy wait to be rescued by the Migrant Offshore Aid Station (MOAS) ship MV Phoenix, some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)

Migrants react after boarding the Migrant Offshore Aid Station (MOAS) ship MV Phoenix some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)

Migrants are helped to cross from their rubber dinghy to a Migrant Offshore Aid Station (MOAS) RHIB (Rigid-hulled inflatable boat) before being taken to the MOAS ship MV Phoenix, some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)

A migrant, who has just been rescued, prays on a Migrant Offshore Aid Station (MOAS) RHIB (Rigid-hulled inflatable boat) whilst being taken to the MOAS ship MV Phoenix, some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)

Migrants reach out to grab hold of Migrant Offshore Aid Station (MOAS) rescuers on a RHIB (Rigid-hulled inflatable boat) before being taken to the MOAS ship MV Phoenix some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)

Migrants on a rubber dinghy wait to be rescued by the Migrant Offshore Aid Station (MOAS) ship MV Phoenix, some 20 miles (32 kilometres) off the coast of Libya, August 3, 2015 (Reuters)