BP oil company has halted much of the work on a damaged well in the Gulf of Mexico, as a tropical disturbance approaches the site. Tropical Storm Bonnie has formed near the Bahamas and has winds of 64 kilometers per hour. Officials expect the storm to move across the oil spill area on Saturday.

Experts with the National Hurricane Center in Miami said it may strengthen in coming days but was unlikely to become a hurricane.

Coast Guard Admiral Thad Allen is overseeing the response to the damaged well in the Gulf. He says crews are preparing for the storm to hit the work area on Saturday, forcing nearly all vessels to suspend their work. "During that time it's very possible we will see wave heights that exceed operational envelope for all platforms. So while it's not a hurricane it's a storm that will have significant impacts and we are taking appropriate precautions," he said.

Some smaller boats already have suspended work skimming oil and have returned to port. Several larger vessels, including two large drilling platforms remain on scene. Wednesday, BP oil officials suspended drilling work on one platform, which is creating a relief well that will be used to seal off the damaged well for good.

Admiral Allen said officials are continuing to monitor the storm to determine whether to issue an evacuation order for offshore crews and vessels.

In case of an evacuation, he said officials have decided to keep a containment cap in place on the damaged well to prevent oil from leaking into Gulf waters. "We have made the determination that it is in the best interest to leave the well capped and we will conduct surveillance to the extent we can. But if we cannot we are prepared to leave the well unattended during this particular event," he said.

Earlier, U.S. officials and BP oil experts had discussed opening vents in the cap to release excess pressure, in case crews were forced to evacuate the site because of a storm. But Admiral Allen said experts are confident the cap does not pose a risk during the storm.

Crews are using remote-controlled submarines to monitor the well head for any signs of leaks or excess pressure. If storm conditions are not too severe, Admiral Allen said vessels operating those submarines may be able to remain on scene for the duration of the storm.