Libya leader Muamer "Gaddafi's outrageous behaviour in the past few days demands we send him back into the cold," Catherine Ashton, EU foreign affairs chief , wrote in an opinion article in the International Herald Tribune.
European Union governments reached consensus on Friday on imposing an arms embargo, asset freezes and a travel ban on Libya, but a formal decision will only be taken early next week.
U.S. President Barak Obama signed an order on Friday prohibiting transactions related to Libya and blocking property, the first major step to isolate the North African leader, who has used army, police and irregular forces to try to crush anti-government protests.
Diplomats at the United Nations have said a vote on a draft resolution calling for an arms embargo on Libya as well as travel bans and asset freezes on its leaders might come on Saturday after U.N. chief Ban ki Moon said it could not wait.
Gaddafi, once branded a "mad dog" by the White House for backing global militants, had spent decades in diplomatic isolation from the West. However in recent years oil exports have helped thaw relations.