Some 800 migrants were plucked from flimsy rubber boats on Thursday, Italy's coast guard said, as Libya-based people smugglers took advantage of a window of good midwinter weather to send them to sea.

Italian coast guard vessel Diciotti and two ships run by humanitarian groups, the Aquarius and the Golfo Azzurro, went to the rescue of a total of six rubber boats in international waters off the coast of Libya, the coast guard said.

Mathilde Auvillain, a spokeswoman for SOS Mediterranee, which co-runs the Aquarius, said they aided a small wooden boat carrying 26 people, mostly Nigerians, on Wednesday, while 123 were taken off a rubber dinghy on Thursday.