Anglo-Dutch oil giant Shell said Monday it would evacuate all its offshore personnel working in the Gulf of Mexico, now threatened by Hurricane Ike.

The company said it had already evacuated 150 workers and would move the remaining 500 between now and Wednesday.

It added that production would continue at a minimum until the evacuation was completed.

BP has also begun to move personnel off its platforms in the Gulf of Mexico. BP and Shell account for a quarter of oil and gas production in the region.

Hurricane Ike was downgraded to a category two storm as it weakened Monday after slamming into Cuba and pummelling its eastern part with gale-force winds and torrential rain.