NATO has conducted hundreds of airstrikes on Libya since March.
NATO has decided to extend its military mission in Libya until the end of September, 2011 as the Western coalition continues to pound targets in Tripoli and its suburbs.
NATO Secretary General Anders Fogh Rasmussen announced the decision during a meeting of the alliance ambassadors in Brussels.
"This decision sends a clear message to the Gaddafi regime. We are determined to continue our operation to protect the people of Libya," said Rasmussen on Wednesday.
The developments come as NATO warplanes have intensified attacks on Tripoli, especially in the Bab al-Aziziya district of the Libyan capital.
The military alliance took over command of the operation from the US in late March.
The UN Security Council resolution 1973 mandated NATO to enforce a no-fly zone to protect civilians from attacks by Gaddafi forces until the end of June.
The US and NATO have unleashed a punishing, UN-mandated offensive against Colonel Muammar Gaddafi to pressure him into giving up power.
NATO has conducted about 9,000 sorties over Libya since it assumed control of a military campaign in late March. The airstrikes by the military alliance have killed dozens of civilians as well as revolutionary fighters.
Critics accuse the West of hypocrisy over the offensive on Libya, along with its silence towards the brutal crackdowns on similar anti-regime movements elsewhere in the Arab world, such as in Bahrain, Saudi Arabia and Yemen.
Experts say the main motive behind the Western attack on Libya is the vast oil reserves of the North African country.
Libya has been the scene of fierce fighting between pro-Gaddafi troops and anti-regime forces since mid-February.
Revolutionary forces want an end to Gaddafi's decades-long rule.