(Recasts with comments on Libya, details on Marines' movement)
By Phil Stewart
WASHINGTON, May 14 (Reuters) - The Pentagon said on Wednesday it has temporarily moved nearly 200 Marines to Sicily from their base in Spain as a precaution due to concerns about unrest in North Africa, bolstering the U.S. ability to respond to any crisis.
The Pentagon declined to single out any countries but two U.S. officials, speaking on condition of anonymity, said American concerns were centered squarely on Libya, where armed groups and Islamists refused to disarm after the 2011 ouster of Muammar Gaddafi.
The Marines are part of a crisis response unit focused on embassy security created after the attack on the U.S. diplomatic compound in Benghazi, Libya, on Sept. 11, 2012, which killed U.S. Ambassador Christopher Stevens and three other Americans.
That force is meant to speed U.S. response times in north and west Africa.
"We're doing this as a contingency because we believe that the security situation in North Africa is deteriorating to a point where there could be threats," said Colonel Steve Warren, a Pentagon spokesman.
Warren did not elaborate. The two U.S. officials, however, told Reuters the move followed widespread concerns about deteriorating security in Libya, as opposed to specific information about an imminent attack.
The Pentagon has in recent months made similar, temporary moves of Marines from the Special Purpose Marine Air-Ground Task Force-Crisis Response, who are mostly based in Spain but also have a contingent stationed in Romania.
Last October, about 200 Marines from the task force also flew to Naval Air Station Sigonella in Sicily for several weeks after U.S. special operations forces captured a senior al Qaeda figure in Libya, triggering unrest.
Three years after the NATO-backed overthrow of Gaddafi, Libya is gripped by political turmoil that has left the government struggling to assert its authority over armed groups and Islamists.
Libya's oil infrastructure remains the target of protests and shutdowns, usually by brigades of former rebels who refuse to recognize the state's authority. Last month, gunmen stormed Libya's parliament.
Earlier on Wednesday, Libyan soldiers in charge of securing the prime minister's office blocked cars from leaving the building in protest at not having been paid.
Warren said the Pentagon's decision to move the forces, along with six aircraft, followed a request from the U.S. State Department.
Warren stressed that while the Marines were "unquestionably" focused on the protection of embassies, he did not rule out the possibility they could be called upon for a different mission.
"These are United States Marines capable of conducting any mission given to them. That said, the focus of this force is the protection of embassies and U.S. personnel," Warren said.
The Benghazi attack has become deeply politicized in Washington, with Republicans accusing President Barack Obama's administration of doing too little to repel the attacks and then trying to protect Obama from political fallout. (Additional reporting by Feras Bosalum and Ulf Laessing; Editing by Bill Trott and Sandra Maler)