The Obama administration has succumbed to pressure from environmental groups and further restricted where Royal Dutch Shell’s Arctic drilling operations could take place.

On Tuesday, the Obama administration blocked Shell from boring two exploratory wells at the same time in the Chukchi Sea this summer. Why? To save the walruses and other marine mammals, according to the Department of the Interior.

The Interior Department ruled Shell’s drilling of two wells nine miles apart would disturb walruses, polar bears and other indigenous species. But Interior’s decision came after pleas from Democrats and environmental activists not to allow Shell to bore wells so close together because they violated a 2013 drilling regulation.

A coalition of environmental groups wrote to the Interior Department earlier this month arguing that “any drilling by two rigs would violate the incidental take regulation” adding that the government’s “decision and the accompanying Finding of No Significant Impact, therefore, are predicated on a presumed drilling scenario that is unlawful and must be rescinded,” the letter continued.

“We ask you to take immediate action to address this basic deficiency in Shell’s drilling plan and permit applications, protect the Pacific walrus, and ensure agency decisions resulting from the review of Shell’s drilling proposal are defensible and lawful,” activists groups led by Earthjustice wrote to the Interior Department.

The same day of the Interior ruling against Shell, Democratic senators wrote to President Barack Obama, echoing eco-group claims that Shell was violating the 2013 regulation. Democratic lawmakers further argued the Obama administration should completely rescind Shell’s approval to drill in the Arctic.

“We reiterate that drilling operations in the Arctic Ocean are unacceptable, and we urge you to rescind Shell’s conditional Exploration Permit in the Chukchi Sea,” Democrats led by Oregon Sen. Jeff Merkley wrote to Obama.

The Interior Department, however, told Shell that some polar bear and walrus “takes” were permissible during their exploratory drilling, but the company would have to drill its wells 15 miles apart instead of the nine miles it was asking for. Also, only one of these wells could be drilled at a time.

Shell’s Arctic drilling operations have been a new focal point for environmentalists looking to stop U.S. drilling operations, especially in areas like the Arctic. The Dutch company got permission from the Obama administration to drill exploratory wells in certain parts of the Arctic earlier this year, which was seen as a blow to eco-activists.

Environmental groups, however, have launched major protests to show their anger at Shell’s drilling plans, and are pursuing legal routes to stymie the company’s Arctic operations or stop them altogether.

“We think the Department of the Interior needs to rescind its approval because it was predicated on this double-drilling (scenario),” Earthjustice attorney Erik Grafe told The Houston Chronicle.

So far, Shell has committed about $1 billion to exploratory operations in the Arctic this year and has already moved one offshore oil rig to the region with another one on its way.

“Our goal is to safely accomplish as much work as we can before the end of the open water season,” a Shell spokesman told The Washington Examiner.

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