The European Union is establishing formal diplomatic contacts with the Libyan opposition by opening an office in the rebel stronghold of Benghazi.

EU foreign policy chief Catherine Ashton will open the office at noon on Sunday. She is in Benghazi for talks with the opposition National Transitional Council.

"Opening an EU office is an important signal of our support for the Libyan people. It is the EU putting words into action," Ashton said when she announced the decision 10 days ago.

Most EU nations have frozen their relations with Moammar Gadhafi's government and withdrawn their diplomats. Hungary, which holds the bloc's rotating presidency, is the only member nation still maintaining a diplomatic mission in Tripoli.

The union has called on Gadhafi to step down, saying he has "lost all legitimacy."