President Obama is weighing a high-profile Oval Office speech on the need for military action in Syria, as opposition to a strike grows on Capitol Hill.

The address would be just his third from the Oval Office since becoming commander-in-chief, a recognition of the challenge the White House faces in winning congressional authorization for military action against Syrian President Bashar Assad.

The White House has yet to publicly commit to an Oval Office address, but signs suggest the president may seek to make his case with a major speech on Syria in the coming days.

Though Obama has the support of congressional leaders on using military force in Syria, opposition in Congress has continued to grow among the rank-and-file from both parties.

The president is on a three-day trip to Europe where he is attending the G-20 summit in St. Petersburg, Russia, but administration officials stressed Thursday that he was focused on winning domestic support for his Syria policy.

Obama canceled a California trip planned for Monday.

“He will remain in Washington to work on the Syrian resolution before Congress,” the White House said.

The president has also been calling lawmakers over Syria during his Europe trip.

Deputy National Security Adviser Ben Rhodes told reporters Thursday there was no “particular speech planned at this point.”

“But we certainly do think that the President will be out there making the case to Congress and the American people,” he added. “He’ll have multiple opportunities to do so.”

Earlier this week, Secretary of State John Kerry said he had “no doubt” Obama would speak on the need for action in Syria from the Oval Office.

Obama is slated to return from Europe on Friday night and the White House has not yet announced his weekend schedule.

Deploying the ultimate bully-pulpit is not without pitfalls for a president who has avoided the traditional prime-time address.

“It’s very risky. If he tries to rally the public and is not successful, it only puts him in a deeper hole,” said Mitchell McKinney, a political communication professor at the University of Missouri. “He doesn’t want to be embarrassed. That would be devastating.”

Obama has been reluctant to use the Oval Office to address the nation, having delivered just two such speeches, both in 2010.

In his first address he discussed the administration’s response to the oil spill in the Gulf of Mexico and in his second touted the end of U.S. combat operations in Iraq.

The president has delivered major addresses from other locations as well, however, memorably announcing the killing of al Qaeda leader Osama bin Laden from the East Room.

Administration officials have eschewed extended addresses from the Oval Office, arguing those speeches no longer carry the same weight in the current 24-hour news cycle.

Others add that Obama should be more concerned with the timing and content of his appeal than where he delivers it.

“That’s more of a Washington consideration than it is with the general public,” said Alan Schroeder, a Northeastern University professor who focuses on presidential communication, of Oval Office addresses.

“If it wasn’t part of the general media coverage — I don’t think people would notice the location. But he’s really got some persuading to do. It’s a really tough case to make,” he added.

Syria presents a unique challenge though for the president, with polls suggesting little public support for military action and uncertainty over whether congressional leaders can wrangle enough votes.

Some of the president’s Democratic allies in Congress have pressed him to make his case to the public, with Sen. Robert Menendez D-N.J. predicting Obama would do so soon.

Advocates of a major address say that the Oval Office provides a feeling of intimacy unlike any other room in the White House and would aid the president as he argues for military intervention to a skeptical public.

President George W. Bush, who like Obama, used Oval Office address sparingly, spoke from behind his desk in 2003 to announce the start of the Iraq War.

President Bill Clinton spoke from the office over U.S. military engagements in Iraq and Haiti, and his predecessor, President George H.W. Bush, did the same to announce allied military action at the beginning of the Gulf War.

Some Democrats also privately acknowledge the risks of an Oval Office address.

“People say if he doesn’t address the nation he’s shirking his presidential duties,” complained one Democratic strategist with close ties to the White House. “But if he doesn’t move the needle — that seems like a tall order — he gets blamed for that too.”