US President Barack Obama has joined with his counterparts in Britain and France, David Cameron and Nicholas Sarkozy, to pledge that the battle in Libya will persist until Moammar Gaddafi is removed from power.

The three Western leaders emphasized their commitment to the military campaign in a joint article.

So long as Gaddafi is in power, NATO and its coalition partners must maintain their operations so that civilians remain protected and the pressure on the regime builds,” the article vowed.

Britain, France and the United States will not rest until the United Nations Security Council resolutions have been implemented and the Libyan people can choose their own future.

The letter published in the Times (UK), the International Herald Tribune and France's Le Figaro.

Obama said it is impossible to imagine a future with Gaddafi ruling Libya.

The joint statement said: It is unthinkable that someone who has tried to massacre his own people can play a part in their future government. The brave citizens of those towns that have held out against forces that have been mercilessly targeting them would face a fearful vengeance if the world accepted such an arrangement. It would be an unconscionable betrayal.

The article declared that Gaddafi must go and go for good, citing that Gaddafi has promised to carry out terrorist attacks against civilian ships and airliners. And because he has lost the consent of his people any deal that leaves him in power would lead to further chaos and lawlessness.”

The article added: We know from bitter experience what that would mean. Neither Europe, the region nor the world can afford a new safe haven for extremists.

The statement also compared the crisis in the Libyan city of Misrata to a medieval siege which is designed to strangle its population into submission.

Meanwhile, NATO has warned that the reluctance of Italy, Spain and The Netherlands to send military planes to conduct air strikes in Libya is hurting the cause against Gaddafi.

Moreover, Gerard Longuet, the French defense minister told French radio that removing Gaddafi would be difficult if not impossible, since it is beyond the beyond the scope of the existing UN resolution on Libya.