Washington: President Barack Obama has vigorously defended American strikes in Libya during a nationwide address. Obama said failure to act would have carried a far "greater price" for the US and also led to a "slaughter" of civilians in the north African nation.

Noting that the US has an important "strategic interest" in preventing Libyan strongman Muammar Gaddafi from overrunning those who oppose him, Obama also declared, "we
have stopped Gaddafi's deadly advance."

Obama ruled out targeting Gaddafi citing the Iraqi experience, warning that trying to oust him militarily would be a costly mistake.

"I, along with many other world leaders, have embraced that goal, and will actively pursue it through non-military means. But broadening our military mission to include regime change would be a mistake," Obama said in his speech that lasted for 27 minutes. He, however, said "there is no question that Libya and the world will be better off with Gaddafi out of power."

He also said the NATO alliance will take command and control of the military operations currently underway in Libya on Wednesday.

"While I will never minimise the costs involved in military action, I am convinced that a failure to act in Libya would have carried a far greater price for America," he said.

"To brush aside America's responsibility as a leader, and more profoundly our responsibilities to our fellow human beings under such circumstances, would have been a betrayal of who we are. Some nations may be able to turn a blind eye to atrocities in other countries. The United States of America is different. And as president, I refused to wait for the images of slaughter and mass graves before taking action," he added.

"Mindful of the risks and costs of military action, we are naturally reluctant to use force to solve the world's many challenges. But when our interests and values are at stake, we have a responsibility to act. That is what happened in Libya over the course of these last six weeks."

The US President said confronted by brutal repression and a looming humanitarian crisis by the Gaddafi regime, he ordered warships into the Mediterranean.

Delving in detail on the military action in battle-torn Libya, Obama said "...tonight, I can report that we have stopped Gaddafi's deadly advance."

America has a crucial strategic interest in stopping Gaddafi from overrunning those who oppose him, he added.

A slaughter would have forced hundreds and thousands of additional refugees across Libya's borders, putting vast strains on the peaceful -- yet fragile -- transitions in Egypt and Tunisia, he said. He addressed the concerns of some of his countrymen opposed to US strikes in Libya. Obama said, “now, despite the success of our efforts over the past week, I know that some Americans continue to have questions about our efforts in Libya. Gaddafi has not yet stepped down from power, and until he does, Libya will remain dangerous."

He also said that America should not alone bear the "burden of action" and other big countries should step up their efforts to prevent any humanitarian crisis in Libya.

"We should not be afraid to act, but the burden of action should not be America's alone," he added.

"Last night NATO decided to take on the additional responsibility of protecting Libyan civilians. This transfer from the United States to NATO will take place on Wednesday," he said, adding that going forward, the lead in enforcing the no-fly zone and protecting civilians on the ground will transition to US allies and partners.

"I am fully confident that our coalition will keep the pressure on Gaddafi's remaining forces. In that effort, the US will play a supporting role, including intelligence, logistical support, search and rescue assistance, and capabilities to jam regime communications," he said.