NATO expressed surprise Tuesday over continued resistance by forces loyal to ousted Libyan leader Moammar Gaddafi after nearly seven months of heavy fighting in the country.

In Sirte, the last coastal city held by pro-Gadhafi forces, forces of the National Transitional Council have captured key landmarks but vicious street fighting continues in their final, "final" push to wrestle control of Gadhafi's home town.

With much of the besieged city reportedly in NTC hands - including its port -- Gadhafi loyalists have lost their last remaining ocean portal for receiving supplies to continue their battle.

"The posture of pro-Gadhafi forces at this stage just does not make sense," NATO military spokesman Col. Roland Lavoie said.

"It is clear that they could not change or influence the outcome of this conflict and they have refused opportunities to be part of a political solution, and basically they have opted to choose to inflict pain to the rest of the population in Libya.

"So from that perspective it just does not make sense to see what these few remaining forces are doing and this could certainly be qualified as surprising, both from a military and a from political point of view."

Fighting was also occurring Tuesday around Bani Walid, a key crossroads town about 100 south of Tripoli.

'In Bani Walid now, where the situation was static until last weekend, NTC forces have started to move toward the outskirts of the small town from which a significant proportion of the population has already left," Lavoie said.

NATO senses impending military victory in its Operation Unified Protector, undertaken with U.N. authority but the end of involvement in Libya may be far from over.

NATO ostensibly undertook military action protect Libyan civilians and rebels from atrocities at the hands of Gadhafi and his followers. But with a political vacuum resulting from the fighting and sharp rivalries among the groups comprising the National Transitional Council, fears of continued chaos and violence have hardly faded.

"The termination of the operation is not dependent on Col. Gadhafi," NATO Secretary-General Anders Fogh Rasmussen said recently. "Actually, he is not the target of our operation. The decisive factor will be the protection of the civilian population."

His point was reinforced Tuesday by NATO spokeswoman Oana Lungescu, who said: "Our mission, as you know, is to prevent attacks and threats against civilians, so we will terminate the mission once we assess that there is no longer a systematic and significant threat and, of course, there are various factors to be taken into account, including the situation on the ground, which is moving fast, and the ability of the National Transitional Council forces to protect civilians themselves.

"Ultimately, like the launch of this operation, the end of the operation will be a political situation."

Libya's National Transition Council formed after pro-democracy demonstrations erupted in February and were met by Gadhafi regime violence. The NTC is composed of various political groups, tribes and gunmen, some of which have been connected in the past with al-Qaida militants.

Rivalry among factions and leaders has reportedly undermined the NTC's ability to form a stable, interim government, which is to oversee national elections at a later date.

One indication of instability is the NTC's ability to safeguard shoulder-fired anti-aircraft missiles that Gadhafi had in weapons depots. The number varies, but reports indicate that thousands are missing and may be on their way to al-Qaida in Africa and elsewhere.

Gadhafi and his sons are believed to be in Libya and will remain sources of instability for the NTC once the final two strongholds fall if they should remain at large. But the real danger for Libya in the near future, and NATO's hoped-for end to military operations, rests with the groups that comprise the country's new political era.

The war that U.S. President Barak Obama in March said would last days rather than weeks is nearing the seven-month mark. A definitive end is still elusive.