U.S. President Barack Obama has called on Libyan leader Moammar Gadhafi to “relinquish power once and for all,” saying the momentum against him has reached a tipping point.

In a statement late Sunday after Libyan rebels pushed into the capital, Tripoli, Mr. Obama said Mr. Gadhafi needs to acknowledge that he no longer controls the country.

Mr. Obama also said the United States will continue to work with the international community to support a peaceful transition to democracy in Libya, and urged the opposition Transitional National Council to include the interests of all the Libyan people.

The European Union, Britain and Italy have all said Mr. Gadhafi's rule is coming to an end, and urged the Libyan leader to step down in order to avoid more bloodshed. Meanwhile, China said Monday it “respects the choice of the Libyan people” and hopes stability returns to the country quickly.

South Africa said Monday it is not supporting the rebels and refuted reports that it had sent a plane to Libya to evacuate Mr. Gadhafi. Foreign Minister Maite Nkoana-Mashabane said Mr. Gadhafi has not and would not ask for asylum in South Africa.

NATO Secretary General Anders Fogh Rasmussen said Sunday the sooner Mr. Gadhafi realizes he “cannot win the battle … the better.”

The International Criminal Court at The Hague confirmed that the rebels had detained Mr. Gadhafi's son Seif al-Islam. The world court was quick to remind the rebels that they had “an obligation to surrender Seif to the ICC.”

The ICC has issued an arrest warrant for Mr. Gadhafi, his son, and intelligence chief Abdullah al-Senussi, charged with crimes against humanity.

Venezuelan president Hugo Chavez on Sunday was one of the rare voices to criticize the events in Libya, and he condemned NATO's airstrikes in the country.

Mr. Chavez has long been a staunch defender Mr. Gadhafi and has denounced the popular uprising, claiming it is an oil grab by Western powers.