BOOTHVILLE, Louisiana (Reuters) - A massive ship converted into a “super skimmer” has arrived in the U.S. Gulf of Mexico to assist with cleanup of the BP oil spill, a government spokeswoman said Thursday.

The 1,100-foot (335 meter)-long ore and oil carrier, dubbed the “A Whale,” is being provided by the owner, TMT Shipping of Taiwan, and can collect 500,000 barrels (21 million gallons) per day of contaminated water, said Chris Coulon, a spokeswoman for the joint incident command.

Financial arrangements of the deal to provide the ship were not immediately available. Coulon said it had not been contracted but added that BP Plc might begin formal contract negotiations if the ship proved to be useful.

The gray and rust-colored tanker, which has a large blue whale painted on its funnel, was converted in mid-June in Portugal to skim spilled oil from the sea but needs to be evaluated by the Coast Guard and others for use in the Gulf.

It rested at anchor in the Mississippi River north of Venice, Louisiana on Thursday. Three horizontal slits used to skim oil were visible at water level on the tanker’s port side.

The ship has been described as a “super skimmer” because it can scoop up millions of gallons of oily water mix every day, much more than skimming vessels already in use.

Rough seas and winds caused by Hurricane Alex, which went ashore in northeastern Mexico late Wednesday, were delaying plans to test the new skimmer.

“They can’t do their testing until the weather has died down,” Coulon said. “They are in close contact with ship owners to proceed with testing as soon as the weather permits.”

At a White House briefing on Thursday, Retired Coast Guard Admiral Thad Allen, the government’s point man for the spill response, said he had “high hopes” for the new skimmer.

About 500 skimmers were in operation prior to the halt of skimming operations as Alex threatened. At the peak, 650 such vessels were in operation.

More than 28 million gallons of oily water mix have been picked up since the beginning of the spill about two and a half months ago, and the cleanup rate has picked up recently. The total a month ago was about 14 million gallons.

Oil from BP’s blown-out well began spewing into the waters off Louisiana after an oil rig exploded on April 20, killing 11 workers.