* Hagel to attend his first NATO defence ministers' meeting
* Post-2014 Afghan deployment on the agenda
* Talks on security training for Libya in early stages
BRUSSELS, June 3 NATO defence ministers concerned about the growing presence of al Qaeda-linked rebels in southern Libya will this week discuss the possibility of training Libyan security forces, U.S. defence officials said on Monday.
Libyan Prime Minister Ali Zeidan requested the assistance at a meeting last week with NATO Secretary General Anders Fogh Rasmussen, who raised the issue with U.S. President Barack Obama in Washington last Friday.
"That was something the president and the secretary general talked at length about, about the way the NATO alliance could perhaps take on a greater role in training for the Libyan security forces," said a senior U.S. official on Defense Secretary Chuck Hagel's plane en route to Brussels.
This week's meeting of NATO defence ministers will be Hagel's first as defense secretary, although prior to becoming the Pentagon chief he chaired the Atlantic Council, a top think-tank on issues important to the Western alliance.
The meeting will consider the scope of NATO support and training of Afghan forces after the full transfer of security authority from the NATO-led International Security Assistance Force at the end of 2014. The group will also hold its first meeting on cybersecurity.
Officials are not expected to decide on the size of the post-2014 Afghan deployment this week.
U.S. defence officials, who spoke on condition of anonymity, said not locking in a number now would give NATO a chance to see how Afghan forces perform this year while they are in the lead for combat operations, and then adjust the number accordingly.
In Libya, NATO played a critical role in toppling Muammar Gaddafi two years ago by imposing a no-fly zone and using air power to try to prevent his forces attacking civilian areas held by rebels.
But Gaddafi's overthrow left Libya with a security vacuum that the new administration has found it difficult to fill. Now, many al Qaeda-linked Islamist militants are believed to have moved into lawless areas of southern Libya after being driven out of northern Mali by a French-led offensive.
Neighbouring Niger has said suicide raids that killed 25 people last month at an army base and desert uranium mine run by France's Areva were launched from Libya, something Libya denied.
Zeidan nevertheless saw fit to ask the alliance for technical support and training for Libyan security forces.
U.S. defence officials said it made sense to consider using the expertise that NATO had gained during its involvement in training Afghan forces.
But they stressed that discussions were in the early stages, that it was unclear where any training would take place, and that NATO countries were not yet being asked to make commitments.