The cap on the damaged oil well captured 11,000 barrels of oil in the last 24 hours, U.S. Coast Guard Admiral Thad Allen said Monday, adding that years needed to restore environments and habitats in the polluted waters.

"We have gone from 6,000 to 11,000," Allen said in a White House briefing, and BP was "trying to increase that production rate, close the venting valves and move to a greater capacity."

Allen, who is overseeing the U.S. government's response to the huge Gulf of Mexico oil spill says BP is anticipating moving another ship into the Gulf area to help move the collected oil, adding that though BP is making progress, it's too early for celebration.

Allen also said even after the well is capped, the United States will be dealing with a spill for another four to six weeks. He acknowledged that the full cleanup would take much longer.

"Dealing with the oil spill on the surface will go on for a couple of months. Long term issues of restoring environments and habitats and stuff will be years."

According to Allen, about 120 linear miles of U.S. coast line have been affected by the oil spill.

The Deepwater Horizon drilling rig, owned by Transocean and leased by BP, sank April 22 some 52 km off Venice, Louisiana, after burning for roughly 36 hours. The untapped wellhead continues gushing oil into the Gulf of Mexico. The White House has called the spill the biggest environmental disaster that the country has ever faced.