President Barack Obama said it would be “outrageous” if the Internal Revenue Service targeted conservative groups and that he would hold the agency accountable, while angrily dismissing the new reports last week over the editing of Benghazi talking points by his administration as a “sideshow” trumped up by his political opponents.

“If, in fact, IRS personnel engaged in the kind of practices that have been reported on, and were intentionally targeting conservative groups, then that’s outrageous. And there’s no place for it. And they have to be held fully accountable,” Obama said during a joint news conference with British Prime Minister David Cameron.

Obama said he would wait to find out the facts before acting but said: “I’ve got no patience with it. I will not tolerate it, and we will make sure that we find out exactly what happened on this.”

During a later gaggle with reporters, White House Press Secretary Jay Carney said the White House counsel’s office was told about the IRS investigation the week of April 22, but neither he nor the president were apprised of it until seeing it in the news on Friday.

He also cautioned that the White House has not seen the inspector general’s report and therefore is still withholding judgment on what it will say. “The ‘if’ is important here,” he said.

On Benghazi, Obama said, “We don’t have time to be playing these kinds of political games here in Washington.” He said the focus on how the talking points were written is a sideshow that distracts from the real question of how to protect foreign service officers who risk their lives to serve.

“We dishonor them when we turn things like this into a political circus,” said Obama, who did not acknowledge the internal editing of the talking points by his administration.

Obama instead said no one knew exactly what had happened in Benghazi in the days following the attack and that he had called the attack an act of terrorism the day after it occurred. He also said his administration disclosed more information about the terrorist attack to Congress days after U.S. Ambassador to the United Nations Susan Rice suggested on Sunday talk shows that it was a spontaneous protest that evolved into something more deadly.

“Who executes some sort of coverup or effort to tamp things down for three days?” Obama asked, accusing his opponents of using the issue for fundraising.

Republican Sens. John McCain of Arizona, Lindsey Graham of South Carolina and Kelly Ayotte of New Hampshire called for a joint select congressional committee to investigate the incident because “the Administration is spinning the American people and stonewalling Congress. This is unacceptable.”

“In light of recent revelations and whistleblower testimony last week before the House Committee on Oversight and Government Reform, it is very clear that we need a Joint Select Committee to resolve these contradictions and answer the many other unanswered questions about this tragedy,” they concluded.

Brendan Buck, a spokesman for Speaker John A. Boehner, R-Ohio, penned a blog post accusing the president of getting his facts wrong several times in the press conference and vowed Republicans would continue to investigate. “Rather than getting some candor from the president today, the American people heard only a number of baseless claims that require fact checking,” Buck said.

Obama’s appearance with Cameron came after the White House was roiled by reports Friday that the IRS targeted tea party groups filing for tax-exempt status for heightened enforcement and that the talking points the administration disseminated after the attacks in Benghazi were more heavily edited than the White House originally portrayed.

The administration and lawmakers in both parties have condemned the IRS actions and vowed to investigate. The Benghazi revelations have the White House struggling to explain why the talking points edited out the knowledge of an al-Qaida link to extremists who participated in the attack and inserted what the administration later acknowledged were false reports of demonstrations preceding the attacks. References to previous attacks in Benghazi and warnings from the CIA were deleted after the State Department complained.

In his prepared remarks, Obama noted the special relationship with the United Kingdom and talked about the White House’s push for a trade pact with Europe, the withdrawal of troops from Afghanistan, the ongoing crisis in Syria, Iran, and foreign aid.