Washington, Oct 21 (IANS): As the new rebel Libyan government announced the death of the former strongman, Muammar Gaddafi, US President Barack Obama hailed the event as a 'momentous day' in the history of Libya."Today we can definitively say that the Gaddafi regime has come to an end," he said in a televised statement from the Rose Garden of the White House. The "dark shadow of tyranny has been lifted."

Obama said the NATO mission in Libya - the United States has participated in NATO's enforcement over a no-fly zone over Libya since the early days of that country's uprising this year - will end soon.

"Without putting a single US (service member) on the ground, we achieved our objective, and the NATO mission will soon come to an end," Obama said.

But he reaffirmed the US commitment to the Libyan people so they can have freedom and opportunity.

Meanwhile, UN Secretary General Ban Ki-moon called on all sides in Libya to lay down their arms and work together peacefully to rebuild the North African nation.

"Clearly, this day marks an historic transition for Libya," Ban said at UN Headquarters in New York, reacting to the reports of the death of the Libyan leader and the end of fighting in Sirte and other cities.

US Strategic think tank Stratfor said Gaddafi's death is symbolically important for the rebels, but the fall of Sirte is even more significant for the effect it will have on the future stability of Libya.

"The shape of the new Libya is highly uncertain," it said. "but with the final holdout of the pro-Gaddafi resistance overtaken, the National Transitional Council (NTC) can now move to form a transitional government."