Britain is pressing for an EU emergency summit declaration calling for Colonel Gaddafi to step down.
In a joint letter with Germany, Foreign Secretary William Hague said the upheaval in the EU's "southern neighbourhood" presents Europe with a challenge and opportunity on a scale matching the revolutions of 1989.
On Libya it said the EU should agree a declaration that "the EU and its member states will not work or co-operate with Gaddafi and that he has to step aside to allow for a true democratic transformation of the country".
The letter came as it was revealed that three members of the BBC's Arabic staff were accused of being spies and held for 21 hours in Libyan military compounds.
The trio were arrested on Monday at an army checkpoint, six miles south of the western city of Zawiyah, before being interrogated, hooded, handcuffed, repeatedly assaulted and subjected to a mock execution.
Their "abhorrent treatment" was condemned by the BBC and the Foreign Office (FCO) who promised a "day of reckoning" for the abuses.
A FCO spokesman said: "This is yet another example of the horrific crimes being committed in Libya. The regime had invited journalists to Libya to see the truth. This truth is even more glaring today than it was before."