Libyan rebels advanced on two fronts on Friday against Muammar Gaddafi troops, who NATO reported still held two cities west of Tripoli, and the UN called for a peaceful transition to end the war.
In Washington, the US House of Representatives voted to forbid the Pentagon from arming, training, or advising the strife-torn North African nation's rebels.
The provision, as part of the Defence Bill, has to go to Senate where it may face stiff opposition and where Republican Senator John McCain denounced the vote as "deeply disturbing".
McCain, a strong supporter of the rebels battling to oust Gaddafi, warned that it "sends exactly the wrong message to Gaddafi and those fighting for freedom and democracy in Libya -- especially since Gaddafi is clearly crumbling."
However, the strength of Gaddafi position appeared still unclear, with fighting continuing and huge pro- and anti-Gaddafi rallies in Libya's towns and cities.
Wing Commander Mike Bracken, the NATO mission's military spokesman, said "anti-Gaddafi forces look to have the initiative and are able to launch successful attacks against pro-Gaddafi forces."
But Gaddafi forces still hold two cities west of the capital Tripoli, Zawiyah and Zuwarah, and are "rearming, regrouping and fighting in places such as Kikla, Misrata and Dafnia," he added via video link from NATO operational headquarters in Naples.
In its latest sortie update, NATO said its aircraft on Thursday attacked close to Tripoli, targeting three anti-aircraft guns and a command and control centre.
Another raid took out military refuelling equipment near the eastern oil town of Brega, the same area where the western alliance attacked eight armoured vehicles and military refuelling equipment on Wednesday.
Tripoli pressed its media offensive with several religious leaders calling for Friday prayers in the capital's Green Square to "beg God to protect Libya against invading crusaders and traitors," a reference to NATO and the rebels.
And UN chief Ban Ki-moon called on Libya's regime to allow a peaceful transition as the rebels went into day three of a NATO-backed offensive to the south and east of Tripoli.
AFP correspondents also reported rebel offensives in the Nafusa mountains to the west of the capital and also around the coastal town of Zliten where NATO targeted a radar position and one artillery piece. It was the second NATO raid there in two days, the Wednesday one taking out eight armoured vehicles.
In the United States, the country's involvement in the Libyan conflict remains unpopular with the public, and the anger of many US lawmakers surfaced on Thursday over President Barack Obama's handling of the conflict.
Republican Representative Tom Cole of Oklahoma introduced the measure to bar US aid to the Libyan rebels, saying in a statement after the vote: "Congress has allowed the president to overreach in Libya."
The statement denounced the US role in the NATO-led, UN-mandated operation in Libya as an "ill-advised adventure."
In Europe, which is carrying out the lion's share of foreign involvement in the fighting, Poland said it had opened diplomatic ties with the rebel National Transitional Council (NTC), installing its ambassador in the eastern stronghold of Benghazi.
Warsaw currently holds the rotating European Union presidency.
The UN's Ban on Thursday urged Libyan Prime Minister Baghdadi al-Mahmudi to stop the fighting, which began in February, and help improve humanitarian conditions.
In a telephone call, Ban stressed "the urgent need to find a way out of the current fighting and alleviate the dire humanitarian situation and work out a transition that could bring peace to all Libyans," his office said.
He also said his special envoy to Libya Abdul Ilah al-Khatib was aiming to reach a peace deal for all Libyans.
Mahmudi had agreed that Khatib should be received in Tripoli "at an early date for urgent consultations," Ban's office added.