Washington (CNN) -- The White House defended to Congress on Wednesday the legality, the costs and accomplishments of the U.S. military mission in Libya.
In a 32-page report titled "United States Activities in Libya," the administration says the cost of military and humanitarian operations through June 3 was about $800 million. It estimates the total cost through September 30 will be $1.1 billion.
The report was drawn up in response to a House resolution that accused President Barack Obama of failing to consult with Congress over the military effort in the North African country.
It denies the accusation by some members of Congress that Obama has violated the War Powers Resolution by intervening militarily for more than 60 days without seeking approval from Congress.
"Given the important U.S. interests served by U.S. military operations in Libya and the limited nature, scope and duration of the anticipated actions, the president had constitutional authority, as commander-in-chief and chief executive and pursuant to his foreign affairs powers, to address such limited military operations abroad," it says.
"The president is of the view that the current U.S. military operations in Libya are consistent with the War Powers Resolution and do not under that law require further congressional authorization, because U.S. military operations are distinct from the kind of 'hostilities' contemplated by the resolution's 60-day termination provision."
The report was accompanied by a two-page letter jointly signed by legislative affairs officials with the departments of Defense and State and directed to House Speaker John Boehner.
"Taken in response to direct appeals from the Libyan people, and acting with a mandate from the United Nations, the United States mobilized a broad coalition, stopped an advancing army, prevented a massacre, established a no-fly zone, and limited the spread of violence and instability in a region pivotal to U.S. security interests," it says.
In response, Boehner spokesman Brendan Buck said, "The creative arguments made by the White House raise a number of questions that must be further explored. 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. With Libya, the president has fallen short on this obligation. We will review the information that was provided today but hope and expect that this will serve as the beginning, not the end, of the president's explanation for continued American operations in Libya."
The exchange of documents came after a bipartisan group of House members filed a lawsuit Wednesday that challenges U.S. participation in the Libya military mission.
Boehner, R-Ohio, said in a letter to Obama on Tuesday that the administration could be in violation of the War Powers Resolution, if it fails to get congressional authorization by Sunday, the 90th day since the mission began and a deadline that some legal experts cite as the deadline set by the resolution.
The lawsuit addresses a long-standing dispute between the executive and legislative branches -- meaning the White House and Congress -- over the powers of the president to send forces to war.
"We are intending through our presence and through this lawsuit to correct an imbalance which exists today, to correct a deficiency in the separation of powers, to correct ... and to firmly establish that Congress is a co-equal branch of government and that the founders made it unmistakably clear they did not intend for the war power to be placed in the hands of an executive," said Rep. Dennis Kucinich, D-Ohio, an anti-war liberal and one of the 10 legislators filing the lawsuit.
Rep. Tim Johnson, R-Illinois, said the legal issue was whether Obama exceeded his authority in committing U.S. forces to the Libya mission.
"Did he act illegally? The answer is yes," Johnson said.
But Wednesday's report from the White House say that U.S. operations are limited to a supporting role in a coalition whose operations are authorized by the U.N. Security Council resolution. They "do not involve sustained fighting or active exchanges of fire with hostile forces, nor do they involve the presence of U.S. ground troops, U.S. casualties or a serious threat thereof, or any significant chance of escalation into a conflict characterized by those factors." it says.
In a letter to Boehner and to the president pro tempore of the Senate, Daniel Inouye of Hawaii, Obama called U.S. support for the NATO-based coalition "crucial to assuring the success of international efforts to protect civilians and civilian-populated areas from the actions of the Gadhafi regime, and to address the threat to international peace and security posed by the crisis in Libya."
He noted that no U.S. ground forces have been deployed, except for operations to rescue the crew of a U.S. aircraft on March 21.
But Kucinich said earlier in the day that the Obama administration must make its case in court. "They can tell it to the judge now," Kucinich said. "They can't claim this isn't a war."
The lawsuit asks the court to "declare that the war in Libya is illegal and order the White House to stop."
The goal of the administration and legislators who support the Libya mission is approval of a new resolution that backs U.S. participation, which would serve as an equivalent to congressional authorization.
The White House has said it was complying with the War Powers Resolution through frequent briefings on the Libya mission, and Wednesday's report cited dozens of them.
Boehner's letter contested that assertion.
"Since the mission began, the administration has provided tactical operational briefings to the House of Representatives, but the White House has systematically avoided requesting a formal authorization for its action," Boehner's letter said. "It has simultaneously sought, however, to portray that its actions are consistent with the War Powers Resolution. The combination of these actions has left many members of Congress, as well as the American people, frustrated by the lack of clarity over the administration's strategic policies, by a refusal to acknowledge and respect the role of the Congress, and by a refusal to comply with the basic tenets of the War Powers Resolution."
Such political wrangling over war powers is common in Washington, with presidents frequently seeking to expand their freedom to commit U.S. forces and Congress battling to exert influence on the process.
Congressional opponents of the mission say that its objective of civilian protection fails to match the stated U.S. goal of Moammar Gadhafi's resignation or ouster and that the Libya situation could become a stalemate.
The White House says incremental progress is occurring through increasing diplomatic, political and military pressure on Gadhafi to step down.
In a coincidence of scheduling, Obama and Boehner are set to play golf together for the first time Saturday, a day after Boehner's deadline for information from the administration and the day before he says it could be in violation of the War Powers Resolution.
CNN's Tom Cohen, Brianna Keilar and Deirdre Walsh contributed to this report.