WASHINGTON (Reuters) - The Pentagon said on Wednesday it may be forced to take extreme measures -- like not paying salaries -- if the Democratic-led Congress fails to pass a $37 billion defense spending bill before lawmakers begin an August recess.

A sign at the Department of Defense is pictured at the Pentagon in Washington, March 25, 2010. REUTERS/Hyungwon Kang

A senior Democratic aide said lawmakers would find a way to get it done. “We will pass it this work period. We have to,” the aide said.

Tensions are growing in the Pentagon about the fate of the bill, which has languished in Congress despite repeated pleas for action by Defense Secretary Robert Gates, who needs to fund a 30,000-troop surge for the Afghan war.

The White House has added to the drama, threatening to veto the bill over $800 million in education spending cuts that were added by the House of Representatives.

“While we hope and expect the Congress will get this done, we also are obligated now to begin seriously planning for the possibility that they don’t,” Pentagon Press Secretary Geoff Morrell told reporters.

He noted that “absent more drastic action” certain Army and Marine Corps spending accounts would run dry in August.

The Defense Department would do everything in its power, Morrell said, to continue to protect the United States and support troops “deployed in harm’s way.”

“It may involve asking a lot of hard-working people in this department to report to duty without an ability to pay them or other extreme measures we would rather avoid,” he said. “But we will get the job done, including in Iraq and Afghanistan and where else we operate around the world.”

Gates raised his concerns with Republicans at closed-door talks on Capitol Hill on Tuesday and afterward Senate Minority Leader Mitch McConnell said, “this is a true emergency.”

“Secretary Gates is not involved in the politics of the add-ons, but he wants the funding for the troops. And he told us clearly today that it has to be done by the end of this month or he will not be able to pay the troops,” McConnell said.