At the meeting, which is classified and for members only, the officials are likely to get an earful from some on the Obama administration’s plans to withdraw all U.S. military forces from Iraq by the end of the year.

“I expect to hear some entertaining versions of history which are absolutely false,” Sen. John McCain (R-Ariz.), the ranking Republican on the Senate Armed Services Committee, told reporters after the Senate GOP’s weekly policy luncheon. “We have squandered the opportunity to keep a residual force in Iraq.”

“The Iranians are already hailing it as a great victory and, for once, they’re right,” he added.

McCain is one of 12 senators who last week sent a letter to Armed Services Committee Chairman Carl Levin (D-Mich.) requesting a hearing on Obama’s Iraq decision “as soon as possible.” In their letter, the 11 Republicans and one independent, Sen. Joe Lieberman (Conn.), wrote that members of Congress need to hear from administration officials on the rationale for the withdrawal.

“Our country has a long history of maintaining a mutually beneficial presence in emerging democracies to promote political stability and the rule of law, which leads to economic vitality not only for the country concerned, but often the entire region,” the senators wrote. “This has always been our primary goal and should remain as such. We need to hear from the Administration on how the decision to withdraw all military forces from Iraq is consistent with this goal.”

Joining Panetta in addressing the lawmakers at Tuesday’s briefing in the auditorium of the Capitol Visitor Center are Deputy Secretary of State William Burns, Director of National Intelligence James Clapper and Martin Dempsey, chairman of the Joint Chiefs of Staff.

The briefing also comes two weeks after Libyan leader Moammar Gaddafi was killed by revolutionaries in his hometown of Sirte.