Nato's Secretary General has said the alliance will enforce the no-fly zone over Libya.
Anders Fogh Rasmussen said the 28 member nations have agreed to act in order to protect Libyan civilians from attacks by Moammar Gaddafi's forces.
He said the Nato operation would proceed in parallel with the bombing campaign carried out by coalition aircraft.
"At this moment there will still be a coalition operation and a Nato operation," Mr Fogh Rasmussen said.
"But we are considering whether Nato should take on that broader responsibility in accordance with the UN Security Council resolution, but that decision has not been made yet."
The decision comes after six days of negotiations and a breakthrough when Turkey, Nato's only Muslim member, agreed to back the plan.
Turkey previously said it did not want Nato to take responsibility for offensive operations that could cause civilian casualties.
Secretary of State Hillary Clinton said the US is taking the next step in military operations against Libya by transferring command and control of the no-fly zone to Nato.
She said the alliance has agreed to protect Libyan civilians, enforce the UN arms embargo and support humanitarian aid efforts there.
She also praised the United Arab Emirates for becoming the second Arab country after Qatar to send planes to help the mission.
Mrs Clinton said she will travel to London next week to co-ordinate the strategy and military operation against Col Gaddafi's.
Sky correspondent Greg Milam said: "It's an announcement we've been expecting for a few days and one Washington was keen to make."