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The White House responded Wednesday to a congressional outcry over U.S. military action in Libya, saying that President Obama has the authority to continue the campaign even without authorization from U.S. lawmakers.

In a detailed, 30-page report sent to Congress, the administration argued that the U.S. has a limited, support role in the NATO-led bombing campaign in Libya. Because U.S. forces are not engaged in sustained fighting and there are no troops on the ground there, the White House says the president is within his U.S. constitutional rights to direct the mission on his own.

The White House said that the mission has cost the U.S. $800 million as of early June and estimated that a total of $1.1 billion will be spent through the beginning of September.

The administration's defense of the Libya mission came in response to a non-binding House resolution passed earlier this month that chastised Obama for failing to provide a "compelling rationale" for U.S. involvement in Libya. A bipartisan group of lawmakers also filed a federal lawsuit.

The resolution gave the administration until Friday to respond to a series of questions on the mission, including the scope of U.S. military activity, the cost of the mission, and its impact on other U.S. wars in Iraq and Afghanistan.

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The report for lawmakers marks the first time administration officials have publically explained why they believe the president can keep U.S. forces involved in the Libya mission without violating the War Powers Resolution. That measure prohibits the military from being involved in actions for more than 60 days without congressional authorization, plus a 30-day extension.

Obama did not seek congressional consent for U.S. airstrikes against Muammar al-Qaddafi's forces, and House Speaker John Boehner sent Obama a letter this week stating that the 90-day window runs out on Sunday.

Boehner, however wasn't satisfied with the report.

"The creative arguments made by the White House raise a number of questions that must be further explored," Boehner spokesman Brendan Buck said in a statement.

"Regardless, the commander in chief has a responsibility to articulate how U.S. military action is vital to our national security and consistent with American policy goals," he said. "With Libya, the president has fallen short on this obligation."

Senior administration officials previewing the report Wednesday said U.S. forces are not involved in the kind of "hostilities" for which the War Powers Resolution says the commander in chief must get congressional approval.

While the U.S. led the initial airstrikes on Libya, NATO forces have since taken over the mission, which is in its third month. However, the U.S still plays a significant support role that includes aerial refueling of warplanes and intelligence, surveillance and reconnaissance work.

White House spokesman Jay Carney said the president expects congressional support for the Libya campaign will continue. With Qaddafi under pressure to leave power, he said now is not the time to send "mixed messages" about U.S. commitment to the campaign.

However, a group of 10 Republican and Democratic lawmakers sued Obama Wednesday for taking military action against Libya without war authorization from Congress. The lawmakers said Obama violated the Constitution in bypassing Congress and using international organizations like the United Nations and NATO to authorize military force.

The Associated Press contributed to this report.