President Obama's proposal to expand offshore drilling has left his environmental supporters in a tricky situation.

Many of the advocacy groups that worked closely with Congress to draft a climate bill oppose the idea on principle. They say offshore drilling poses environmental threats through oil spills, and they prefer energy solutions that don't emit carbon gases.

But they may have accepted coastal drilling as part of a broader plan to ensure that climate legislation gets through the Senate this year. By highlighting his proposal to expand oil drilling along the Atlantic and Arctic coasts in a standalone speech, the President pushed some of his most ardent supporters into a tight corner.

Their reaction ranged from applause to outrage, but most stopped short of abandoning the ongoing climate change talks in the Senate.

The League of Conservation Voters, which gave the President an outstanding B+ for his work on the environment last year, called the announcement highly disappointing.

"Opening our coastlines for additional offshore drilling will continue the failed energy policies of the past and do nothing to create the new clean energy jobs of the future," President Gene Karpinski said in a statement.

The Natural Resources Defense Council and Sierra Club issued similar rebukes couched in praise of Obama’s continuing work to pass a climate and energy bill through Congress.

"There are lines that people can cross that will cause Sierra Club and certain Senators to not be able to support the bill," Sierra Club spokesman Josh Dorner said.

When asked whether offshore drilling is on that line, Dorner replied that "it would really depend."

Sens. John Kerry (D-Mass.), Joseph Lieberman (I-Conn.) and Lindsey Graham (R-S.C.) have not yet revealed the details of their bipartisan plan.

What puzzled Mark Ferrulo, whose nonprofit Progress Florida opposes offshore drilling, is that the President didn't hold off on the announcement until the Senators had done so.

"If you've got chips you want to play with, it seems he's given them away without anything in return," Ferrulo said.

Other groups like the Blue Green Alliance, a coalition of labor unions and environmental groups, have stayed away from the divisive issue. They continue to support efforts to pass a bill in the Senate.

Some within the Alliance favor offshore drilling for the jobs it would create, a reason cited by President Obama when he tried to sell the plan at Andrews Air Force Base Wednesday.

"The bottom line is this: Given our energy needs, in order to sustain economic growth, produce jobs, and keep our businesses competitive, we're going to need to harness traditional sources of fuel," Obama said.

For environmentalists like Carole Holley, who helps lead the Alaska program at Pacific Environment, that is a compromise that goes too far.

"It's an irony that they're trying to pass a bill that really is pushing to cut down greenhouse gas emissions and yet allows for expanded offshore drilling," she said.

President Obama did appease some environmental groups by excluding Alaska's Bristol Bay and requiring a scientific inquiry before offshore drilling can happen on the Arctic Coast.

Based on that caveat, the Alaska Wilderness League offered the plan a rare thumbs-up.

"This morning's news about offshore drilling on Alaska’s Arctic coast indicates that the Obama administration intends to make sound decisions based on science," the group said in a statement.

Ambreen Ali writes for Congress.org.

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