John Boehner: US House to open new Benghazi inquiry
The US House speaker has said he will convene a congressional special committee to investigate the White House response to the 2012 attack on the US consulate in Benghazi, Libya.
Republican John Boehner said the Obama administration was "obstructing the truth" on the matter.
Republicans say the Democratic Obama administration mislead the public on the nature of the attack.
Four Americans including US Ambassador Chris Stevens were killed.
"Americans learned this week that the Obama administration is so intent on obstructing the truth about Benghazi that it is even willing to defy subpoenas issued by the standing committees of the people's House," Mr Boehner wrote in a statement.
"These revelations compel the House to take every possible action to ensure the American people have the truth about the terrorist attack on our consulate that killed four of our countrymen."
Mr Boehner said he would hold a vote in the House on whether to convene a special committee. The House is controlled by the Republicans and is all but certain to approve the request.
The 11 September 2012 attack, in which gunmen stormed the US compound and set it on fire, has become a political lightning rod.
The White House initially said the attack grew out of violent protests against an anti-Islam video produced in the US.
Further inquiry found that it was an organised attack planned by local militias, although an extensive New York Times investigation did indeed find some of the attackers were motivated by the film.
The Republicans have accused the Obama administration of covering up the involvement of militant groups in the days after the attack in order to protect President Barack Obama's 2012 re-election campaign.
'Known security shortfalls'
They have also sought to use the Benghazi incident as a cudgel against then-Secretary of State Hillary Clinton, who is weighing a 2016 presidential run.
On Friday, Mr Boehner said emails released this week indicated the White House had withheld documents from congressional investigators.
In one email of the estimated 40 obtained and distributed by a conservative group called Judicial Watch, Ben Rhodes - a mid-level White House national security aide - said the White House should stress "that these protests are rooted in an Internet video, and not a broader policy failure".
The 14 September 2012 email came just days before then-UN Ambassador Susan Rice said on several Sunday news programmes that the Benghazi attack was the result of a protest over the anti-Islam video.
Following the release of the emails, White House press secretary Jay Carney said that message referred to the overall situation in the Arab world, and not explicitly Benghazi.
Also on Friday, Republican Congressman Darrell Issa, chairman of the House oversight committee, said he planned to subpoena Secretary of State John Kerry to testify on the matter.
Mr Kerry was a US senator from Massachusetts at the time, not a member of Mr Obama's cabinet.
In January, a separate US Senate cross-party committee found the attack in Benghazi could have been prevented.