WASHINGTON -- The White House finally made its case to Congress on why it doesn't need lawmakers' approval to forge ahead with military operations in Libya: Because we're not at war.

Senior administration officials said Wednesday that the fact that the U.S. is only playing a support role in the NATO-led military effort in Libya -- that is, no U.S. troops on the ground and no potential for casualties -- and only plans to be involved for a short time means Obama doesn't need congressional authorization per the War Powers Act to proceed.

"We are confident that we're operating consistent with the resolution," an administration official said on a conference call with reporters. "That doesn't mean that we don't want the full, ongoing consultation with Congress or authorization as we move forward, but that doesn't go to our legal position under the statute itself, and we're confident of that."

The call came hours before the White House submitted a detailed, 32-page report to Congress that maps out the administration's legal justification for Obama continuing to call the shots on Libya without congressional approval.

See below for a copy of the report and Obama's accompanying letter to Congress. Lawmakers will be poring over it for details primarily on two things: 1) the costs of U.S. military operations, which the report puts at $715.9 million, from mid-March through June 3, and 2) the goals of U.S. involvement. The report gives a general sense of military goals as being "to protect civilians and enforce the terms" of the United Nations Security Council resolution, while political goals are to work with the international community "to bring stability to Libya and allow the Libyan people to reclaim their future."

Brendan Buck, a spokesman for House Speaker John Boehner (R-Ohio), said a quick read of the report raises a number of questions about "the creative arguments" being made by the White House.

"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," Buck said. "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.”

Lawmakers in both parties have grown frustrated with Obama for not consulting Congress on the U.S. role in the NATO-led bombing campaign in Libya, which began in March when Libyan leader Muammar Gaddafi began threatening violence against potentially thousands of his citizens as they protested his regime. The White House has maintained all along that a massacre was averted because the U.S. took quick action and joined with NATO to stop Gaddafi's forces.

Rep. Dennis Kucinich (D-Ohio), one of Obama's most vocal critics on Libya, led a bipartisan group of lawmakers in filing a lawsuit against Obama earlier Wednesday over the constitutionality of launching military operations without congressional approval. He later issued a statement in response to the White House report.

“The White House claim that the war is not war is not a legal argument. It is a political argument," Kucinich said in a statement. "The legal argument will hopefully be addressed by the courts. Today, I, along with 9 of my colleagues, filed suit in federal court challenging the rationale that has brought our nation to an Orwellian war that is not war."

Boehner also warned Obama Tuesday that he may be in violation of the War Powers Act by Sunday if he doesn't seek congressional authorization by then. Sunday marks 90 days of U.S. operations in Libya; per the War Powers resolution, a president is required to obtain congressional approval for continued action by this date.

But the White House is sending a clear signal that they don't believe they need that authorization. During the conference call, the administration official ticked off numerous reasons why U.S. involvement in Libya doesn't constitute a violation of the War Powers resolution.

"We're not engaged in any of the activities that typically over the years in war powers analysis is considered to constitute hostilities within the meaning of the statute," said the official. "We're not engaged in sustained fighting. There's been no exchange of fire with hostile forces. We don't have troops on the ground. We don't risk casualties to those troops. None of the factors … has risked the sort of escalation that Congress was concerned would impinge on its war-making power."

Instead, the U.S. is only providing intelligence and refueling capabilities, said the official. And while that role brings "a set of unique capabilities" to the international effort, it is a far cry from the responsibility that NATO has for enforcing the no-fly zone and protecting civilians militarily.

"The bottom line is that lives have been saved," said a second administration official. "The president was very clear at the front end of this effort that the U.S. contribution would be limited in scope and duration; that there would be no U.S. troops on the ground in Libya. And that, of course, is a commitment that the president has kept and will continue to keep."

You can read the White House report here:

A copy of Obama's letter to Congress is here: