Tripoli , Libya ( CNN ) -- Fighters pushed Sunday to the outskirts of one of Moammar Gadhafi 's last bastions of support , setting the stage for possible clashes ahead of this week 's deadline for loyalists of the ousted leader to surrender . Libya 's new leaders gave Gadhafi loyalists in Sirte , Bani Walid and a handful of towns until Saturday to surrender or face military force . `` We 're giving them a chance to come forward and negotiate surrender , '' Col. Ahmed Bani , spokesman for the National Transitional Council 's defense ministry , told reporters Sunday . But there were indications that fighters were planning to enter Bani Walid , where a powerful tribe is sympathetic to Gadhafi , before the deadline . One of Gadhafi 's sons , Saadi Gadhafi , told CNN 's Nic Robertson in a phone conversation that negotiations aimed at a cease-fire had been going well , but that an `` aggressive '' speech broadcast by his brother , Saif al-Islam Gadhafi , a few days ago caused talks to break down . He said he saw no further point in negotiating and believes the NTC is ready to go into Bani Walid . NTC negotiator Abdallah Kinshel said the planned talks fell apart after local leaders refused to come to the designated meeting spot -- a mosque outside of town -- and demanded the NTC fighters come into the town unarmed . The anti-Gadhafi forces refused . `` As far as we are concerned , negotiations are over from our side , '' Kinshel said . `` Military commanders must determine what the next steps will be . '' Asked his location , Saadi Gadhafi said he is `` a little bit outside '' of Bani Walid but had been moving around . `` It seems that his options are running out , '' Robertson said . Saadi Gadhafi said he had not seen his father or brother for two months . He said he is `` neutral '' and not on his father 's side or that of the rebels , but remains `` ready to help negotiate a cease-fire . '' NTC fighters positioned outside Bani Walid said they remain unwilling to shed blood or fire shots . `` Some tribal leaders and many of the residents have surrendered their weapons , but there are still many loyalists who are protecting Moammar Gadhafi and his sons , '' National Transitional Council media coordinator Adel Zintani said . The deadline was extended by a week to curb further bloodshed and prevent further destruction , military commanders have said . `` This extension does not mean we are unaware of what Gadhafi 's accomplices are up to , '' NTC chairman Mustafa Abdul Jalil said at a news conference , countering earlier criticism that a grace period might give Gadhafi 's forces to regroup . But Gadhafi 's spokesman , who has not been seen since Tripoli fell , said key tribal leaders in Bani Walid remain loyal to the ousted leader . Musa Ibrahim , in a telephone call from an undisclosed location , told Reuters that the transitional council 's messages `` are not being heeded here in Bani Walid . '' Ibrahim also told Reuters that Gadhafi remained in Libya , though he said he did not know where . He did say Gadhafi was well defended . Anti-Gadhafi forces were positioned around the former leader 's hometown of Sirte as well as Bani Walid , Jalil said Saturday . Asked to comment Sunday on a report that the NTC knows Gadhafi 's whereabouts , Col. Bani refused to do so . Ali Tarhouni , interim deputy prime minister and oil minister of the NTC , said Bani Walid was close to falling . `` It 's possible , although we are not sure , that the Bani Walid ( tribe ) has joined the revolution , and now it 's under control of the revolutionaries , '' he said . Anti-Gadhafi fighters from the east pushed toward Bani Walid Saturday with virtually no resistance . They were able to reach El Mardum , which sits on the border of Bani Walid province and is home to Khamis Gadhafi 's 32nd Brigade base . The anti-Gadhafi forces entered the base and arrested three men in civilian clothes they claim were loyalists . They also took seven armored personnel carriers . Tarhouni said Libya 's new leadership will move their headquarters from Benghazi to Tripoli this week to begin implementing political plans to shape a new future . But for the time being , guns trump government on the streets of the capital . Tripoli has become a city of checkpoints , weapons and no real authority as the threat of Gadhafi 's loyalists lingers . Jittery and suspicious anti-Gadhafi fighters blocked a road Saturday where a drive-by shooting occurred earlier . They collected weapons and registered them at police stations . Those who called themselves rebels just a week ago were now working with Tripoli 's law enforcement authorities . With Gadhafi 's armories emptied , guns -- always in large supply in Libya -- have proliferated on the streets . Those who want to carry weapons now must be issued identification cards , but the selection process is not centralized -- neighborhood councils are making that decision . A group called the Tripoli Revolutionary Council is trying to exert control over the city , creating the potential for further conflict with the established National Transitional Council in a volatile situation . Tarhouni announced Saturday the formation of the Supreme Security Committee , which held its first meeting Friday . Among the priorities for the committee were the protection of public institutions and weapons in Tripoli . The transitional council , meanwhile , is trying to get Libya 's oil-dependent economy going again . It expects to restart oil production at the Misla and Sarir oil fields in less than two weeks , Tarhouni said . In related news , Cuba withdrew its ambassador from Libya , saying it does not recognize the NTC . CNN 's Arwa Damon , Ben Wedeman , Mohammed Tawfeeq and Frederik Pleitgen contributed to this report .
NEW : Gadhafi 's son says he is willing to negotiate a cease-fire . `` As far as we are concerned , negotiations are over , '' NTC negotiator says . `` No comment '' on a report that the NTC knows Gadhafi 's whereabouts . Libya 's new leaders have given Gadhafi loyalists until Saturday to surrender .