The rebels admitted they were running low on ammunition as they struggled to hold off an assault by the Libyan leader's forces in the town of Zliten, some 120 kilometres east of the capital Tripoli.
Abdul Wahab Melitan, a rebel spokesman in the port city of Misrata near Zliten, said forces loyal to strongman Qadhafi had on Sunday launched an assault on their positions in the Souk Telat area, killing three and wounding 15.
"The rebels lack ammunition to advance and we do not want to risk losing any ground," Melitan said.
The rebels on Tuesday punched into the centre of Zliten, sparking fierce clashes but later pulled back to the edge of the city.
In Tripoli, Prime Minister Baghdadi Mahmudi told reporters that government troops had recaptured the strategic town of Bir Ghanam, southwest of the capital, from insurgents.
"Life is back to normal in Bir Ghanam, and today it is under the full control of the regime," Mahmudi said.
But rebels were in control of the town early Monday, an AFP journalist said.
"The rebels are controlling the checkpoints. There are no shots," the journalist said, adding that NATO warplanes were flying overhead.
Rebels from the Berber-dominated Nafusa mountain range south of Tripoli claimed the capture of Bir Ghanam just 80 kilometres from the capital on Saturday, as they pushed further east.
The rebels have been using the Nafusa as a springboard to advance on Tripoli but have encountered strong resistance from fighters loyal to Qadhafi.
Mahmudi also condemned the intensification of NATO raids on Tripoli and other cities, claiming that the alliance no longer "differentiates between civilian and military sites."
Mahmudi criticised the National Transitional Council (NTC), the rebels' de facto government, and the security situation in the rebel-controlled east, especially after last month's assassination of General Abdel Fatah Yunis, a long-time Qadhafi ally before he defected.
The premier claimed that the "decision-making and the real forces in the field are in the hands of Islamist extremist groups."
Since the beginning of the revolt, the Qadhafi regime has portrayed the five-month-old uprising as an Al-Qaeda plot.
Mahmudi also claimed that most NTC members had left the country, saying: "I defy the NTC to meet even once during Ramadan," the Muslim month of fasting.
Meanwhile, a rebel source at Al-Qusbat, around 90 kilometres (55 miles) east of Tripoli, said that town was still under siege.
A group of rebels on Thursday overran Qadhafi forces based in one of the town's schools, but since then the rebels have been battling to hold on to their gains.
Meanwhile, the London Times reported on Monday that a rebel blueprint for a post-Qadhafi Libya would retain much of the current regime's infrastructure in the hope of averting an Iraq-style descent into chaos.
A 70-page plan prepared by the NTC with help from Western powers and seen by the paper concedes they have little chance of toppling the long-serving ruler but that internal divisions will force him out.
In that event, the rebels plan to establish a 10,000-15,000 strong "Tripoli task force" to secure the capital and capture prominent Qadhafi supporters.
Around 5,000 policemen will be recruited to serve as the interim government's security forces, according to the plan.
The rebels claim that 800 current Qadhafi government officials have already been recruited to their cause, and could form a key plank of a post-conflict security apparatus, the paper reported.
The document also maps out how telecommunications, power and transport infrastructure will be secured in the immediate hours after the regime's collapse.
The plan relies heavily on defections from the old regime, which threatens to cause friction with those within the rebel faction who want a complete purge of the existing order.
Copyright AFP (Agence France-Presse), 2011