Deputy Prime Minister Nick Clegg has called for a swift European response to the bravery of populations in North Africa fighting for democracy.
"They have created an unexpected and game-changing turn of events in Europe's neighbourhood: we must provide a game-changing response." he said in a speech in Brussels.
He warned: "Despite our good intentions, we Europeans have failed in the past by allowing autocratic regimes to get away with making a pretence of reforming. We have imposed minimal conditionality and then failed to insist even on those low standards.
"We have failed because our support for North African countries has not been based strongly enough on the values of open societies. We have supported the important goals of economic opening and reform, but the EU has done nothing like enough to use its weight to encourage open, plural societies more broadly."
Now, he said, it was time to capitalise on democratic change and offer support to promote change:
"As Prime Minister David Cameron has said, you cannot impose democracy from 30,000 feet. But you can support democracy from across borders and across the Mediterranean. Being adherents of the international rule of law does not mean being neutral about the kind of world we want to see and the kind of nations we want to deal with: open, free, democratic society.
"We should never hold back from advocating our belief that freedom and the rule of law are the best guarantees of human progress and economic success, and that each country should find its own path to achieving peaceful change."
Mr Clegg, addressing a selected audience of Brussels business leaders and Eurocrats, went on: "This is a precious moment of opportunity for the region. Precious because it is the people, especially the young people, who are speaking up, and they are doing so for the most part peacefully and with dignity.
"They are showing that there is more to politics in the region than the choice between repression and extremism.
"It is precious, but potentially fragile too. There is no certainty about the outcome. This is why Europe must play its part."