LONDON, March 9 (UPI) -- Washington and London agreed to consult with NATO on steps needed to address the crisis in Libya, the British Ministry of Defense said.
Libyan leader Moammar Gadhafi remains defiant as fighters loyal to his regime clash with rebel forces in key cities across the country.
The U.N. Security Council last week referred Gadhafi to the International Criminal Court for alleged crimes against humanity. Gadhafi's forces allegedly fired on civilian demonstrators during February protests.
British Prime Minister David Cameron spoke with U.S. President Barack Obama about the crisis in Libya, a key oil exporter.
"The prime minister and the president agreed to press forward with planning, including at NATO, on the full spectrum of possible responses, including surveillance, humanitarian assistance, enforcement of the arms embargo and a no-fly zone," the British Ministry of Defense said in a statement.
Military leaders in the United States expressed apprehension about imposing a no-fly zone over Libya, saying such action would be considered an act of war.
U.S. Sen. Dick Lugar, R-Ind., the ranking Republican on the Senate Foreign Relations Committee, said military action in Libya should be reviewed carefully.
"The United States should not, in my view, launch military intervention into yet another Muslim country, without thinking long and hard about the consequences and implications," he said. "Given Libya's strategic importance, owing to its oil and its location, a misstep would be very costly."
Libyan sources told London's pan-Arab daily Asharq al-Awsat that Western powers were trying to negotiate behind the scenes to get Gadhafi to step down.
"Let me reiterate what has been said before, Col. Gadhafi is not a president or a traditional ruler that can step down or be removed from power," the source was quoted as saying. "He previously said that if he were a president he would have thrown his resignation in the face of those who are calling for this."