Top U.S. Gulf of Mexico oil producer Shell said it had halted production at three of its U.S. Gulf of Mexico deepwater platforms after a leak shut pipelines connecting the platforms.

Shell said its Mars, Ursa and Olympus platforms have been shut-in. The three are designed to produce up to 410,000 bbl/d combined, according to data on the company's website.

"Shell is coordinating with local authorities and mobilizing personnel and equipment to assess the situation," the company said in a statement. It did not estimate when the pipelines might resume operation.

The three platforms deliver Mars sour crude, a grade prized by oil refiners in the United States and Asia. Shell said it was evaluating "alternative flow paths" to move the oil to shore via other pipelines.

Shell shut its Mars and Amberjack Pipelines due to a leak at the Fourchon booster station, it said. The Fourchon Booster Station helps increase the pressure and crude oil flow to onshore storage facilities in Clovelly, La.

A spokesperson for the Port Fourchon Commission was not immediately available to comment on the booster station.

Offshore