Italian coast guards were trying to reach a fishing boat packed with some 100 migrants adrift off the coast of southern Italy in gale-force conditions.
Coast guards said the boat was around 70 nautical miles southeast of Crotone, but getting too close to it could cause an accident because of the size of the waves.
Four merchant ships were in the area, along with a coast guard patrol boat and an Italian navy frigate.
"We are waiting for a break in the weather to operate safely," coast guard spokesman Filippo Marini said.
The Beaufort wind force scale in the area was 8 out of 12, which can create waves up to 7.5 metres high.
Marini said there were women and children on the 20-metre boat, spotted on Sunday after a satellite phone call from an Egyptian national on board.
Hundreds of migrants drowned in two shipwreck tragedies in October near the Italian island of Lampedusa after the heavily overcrowded vessels capsized.
