A contentious issue emerging in the Gulf oil spill cleanup is the number of skimming vessels in the Gulf – or lack thereof.

According to the Deepwater Horizon Response statistics, there are currently "more than 510" skimmers involved in the ongoing response effort.

But many have criticized BP and the U.S. Coast Guard for not bringing more U.S. – and foreign – skimmers into the region to help.

Some politicians, like Sen. Kay Bailey Hutchinson, R-Texas, have complained that the Jones Act, a 1920 maritime law that promotes U.S. shipping interests, is prohibiting foreign flagged vessels from entering the Gulf of Mexico to help in the cleanup effort.

"Over 20 countries have offered response vessels and expertise to assist in the cleanup of the Gulf, but because of the 1920 Merchant Marine Act, known as the Jones Act, foreign vessels are prohibited from operating within three miles of the U.S. coastline except after going through an extended process for waivers," Hutchinson said at a congressional hearing Wednesday.

However U.S Coast Guard Admiral Thad Allen, commander of the federal spill response, says that the Jones Act has not impeded foreign flagged ships from helping out. During a briefing Wednesday, Allen said that the Jones Act had not created "inhibitions or constraints" on the cleanup.

During an interview with msnbc.com Tuesday, Coast Guard spokesman Capt. Ron Lebrec noted that while Allen doesn’t believe vessels need a waiver from the Jones Act to help with the spill, regardless, the Coast Guard has established a expedited process if it is determined that waivers are required.

"The Jones Act hasn’t impacted any vessels coming to this response," he said. "And we have taken proactive steps to ensure it does not become an issue."

Click here to read an editorial about the skimming vessels from the Times-Picayune:
Cut red tape and get more skimming vessels to oil spill: An editorial

-- Petra Cahill, msnbc.com