Troops loyal to Libya's new leaders maintained strong momentum Tuesday against pro-Moammar Gadhafi holdouts as they planned an assault on one loyalist city and moved into another without resistance.

A National Transitional Council official said fighters were planning a major assault on Bani Walid, a northern town still held by Gadhafi loyalists. "Our fighters are planning a massive attack today to bring the siege to an end," Abdallah Kenshil said.

Meanwhile, NTC fighters moved into Sabha, a southern town long regarded as a pro-Gadhafi stronghold, and have met no resistance so far, according to a CNN team that accompanied the forces.

This comes as an audio message purported to be from the deposed Libyan leader said the Gadhafi political system represented the people's will and could not be overthrown.