The teams are said to be there 'primarily' to gather information. But they will advise the rebels on how to secure a handover of power and set up a democratic government.
'Once we get to the stage where we have a transition, part of what we're looking at is supporting that transition,' a source said.
Britain has also stepped up its military preparations, sending the frigate Westminster and the Royal Fleet Auxiliary ship Argus to the area.
Britain still has three Chinook helicopters in Malta. And military planning for a No Fly Zone gathered pace yesterday when the North Atlantic Council tasked Nato military authorities with providing a range of plans yesterday.
Britain is likely to play a central role in any military action since the continuing evacuation and humanitarian aid flights are all being coordinated by a Joint Force Headquarters in Malta.
It is understood that the UK is more likely to supply air-to-air refuelling planes and AWACS spy-in-the-sky aircraft to any No Fly Zone operation.
These planes are already flying around Libya's air space monitoring Colonel Gaddafi's use of his air force and helicopter gunships.
But a senior security official yesterday made clear that Britain will not be supplying arms and ammunition - in contrast to last Monday when Prime Minister David Cameron said he would consider arming the opposition - an off-the-cuff reply to an MP which led to accusations of sabre rattling.
Military liaison officers also accompanied International Development Secretary Andrew Mitchell yesterday as he toured humanitarian camps on the Libyan border with Tunisia.
Officials say they are 'very concerned' by the lack of information about western Libya, the area under the command of Gaddafi's forces and where aid agencies have been denied access.
Shops and banks are still operating in Benghazi and other towns in the east and rebel forces have access to food and medicine.
Diplomats are also monitoring rebel-held towns such as Misurata, which is under attack from Gaddafi's forces from both sides.
There, food and medicine are feared to be running out - which could lead to calls for air drops of aid.
The Foreign Office says fewer than ten Britons who want to leave are still in Libya and yesterday finally warned Britons against going to the country.