The army is waiting for the weather to subside before making any attempt to transfer 161 migrants ashore from a cargo ship that rescued them on Sunday.

A pregnant woman who was in the group was airlifted to hospital late last night in dramatic operation by the AFM.

The cargo ship yesterday dropped anchor in Anchor Bay, which is not as exposed to the rough seas and strong winds. But attempts by the army to transfer the migrants aboard two military boats in the afternoon were unsuccessful because of the inclement weather.

An army spokesman said a request for blankets was made between Sunday and yesterday but this could not be met because of rough seas that made any shipment impossible.

The 162 migrants - 133 men, 28 women, one of whom is pregnant, and a boy - on Sunday sent a distress signal by satellite phone to the army from a location at sea about 59 nautical miles south of the island. The army immediately sent a patrol boat but, as the weather worsened, it instructed a cargo ship in the vicinity to take them aboard from the small wooden boat they were travelling in. The cargo ship then began approaching the island but was unable to safely unload the migrants onto the patrol boat. It consequently spent the night anchored off the island.

But a spokesman for the AFM said the pregnant woman was airlifted from the cargo ship by helicopter and transferred to hospital in a difficult operation in gale force winds at about 10.30 p.m.

If today's forecast for more rain and winds persists, the operation will be further hampered.

The migrants are the first boatload rescued this year.