TRIPOLI — Dwindling supplies of food and medicine are a "time bomb" in parts of Libya held by Moammar Gadhafi, with some food stocks likely to last only weeks, the U.N. humanitarian coordinator for Libya said on Tuesday.
"I don't think there's any famine, malnutrition," Panos Moumtzis told Reuters.
"But the longer the conflict lasts, the more the food stocks supplies are going to be depleted, and it's a matter of weeks before the country reaches a critical situation," he added.
Meanwhile, South African President Jacob Zuma said on Tuesday after talks with Gadhafi that the Libyan leader is emphatic that he will not leave the country, leaving prospects for a negotiated end to the conflict looking dim.
Within hours of Zuma's departure from Tripoli late on Tuesday, Libyan television reported that NATO aircraft had resumed attacks, striking what it called civilian and military sites in Tripoli and Tajoura, just east of the capital.
Zuma was in Tripoli to try to revive an African "roadmap" for ending the conflict, which started in February with an uprising against Gadhafi and has since turned into a war with thousands of people killed.
The talks produced no breakthrough, with Gadhafi's refusal to quit — a condition the rebels and NATO have set as a pre-condition for any ceasefire — still the sticking point.
"Col. Gadhafi called for an end to the bombings to enable a Libyan dialogue," Zuma's office said in a statement. "He emphasized that he was not prepared to leave his country, despite the difficulties."
Zuma also said Gadhafi's personal safety "is a concern" — a reference to NATO strikes which have repeatedly hit the Libyan leader's Bab al-Aziziyah compound and other locations used by the Libyan leader and his family.
Previous truce proposals
In April, Zuma led a delegation of the African Union to Tripoli with an AU proposal for a truce. Gadhafi said he would accept the truce but quickly ignored it and resumed his attacks, while the rebels rejected the cease-fire out of hand because it did not include Gadhafi's exit from power. Since then many cease-fire efforts have failed for similar reasons.
In Benghazi, the de facto rebel capital, rebel Foreign Minister Fathi Baja rejected the African Union plan. "We refuse completely, we don't consider it a political initiative, it is only some stuff that Gadhafi wants to announce to stay in power," he told The Associated Press.
He said he believes Zuma is in Tripoli to negotiate an exit strategy for Gadhafi, though Zuma's office denies that. Baja also said the rebels would launch an offensive against Gadhafi soon.
For decades Gadhafi has identified Libya as an African as much as an Arab nation. He disbursed millions of dollars in aid to African nations and built himself up as a leader of the continent.
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Zuma was greeted with all the requisite fanfare by Gadhafi's beleaguered regime. Dozens of Gadhafi supporters, bused in for the welcoming, waved green Libyan flags and chanted slogans denouncing the NATO bombing campaign against Libyan government targets.
NATO temporarily lifted its no-fly zone over Libya to allow Zuma's South African air force plane to land at the main military air base next to Tripoli.
'A lot of killing'
Earlier in Rome, eight Libyan officers, including five generals, appeared at an Italian government-arranged news conference, saying they were part of a group of up to 120 military officials and soldiers who defected from Gadhafi in recent days.
The defections come two months after that of Libyan foreign minister and former espionage chief Moussa Koussa and the resignation of senior diplomat Ali Abdussalm Treki.
In Rome, one of the defecting officers, who identified himself as General Oun Ali Oun, told reporters: "What is happening to our people has frightened us.
"There is a lot of killing, genocide ... violence against women. No wise, rational person with the minimum of dignity can do what we saw with our eyes and what he asked us to do."
Libyan U.N. Ambassador Abdurrahman Shalgam, who has also defected from Gadhafi, said all 120 of the military personnel were outside Libya now but he did not say where they were.Story: Libyan rebels distribute rules on POW treatment
Libyan television later reported that coalition aircraft struck what it called a number of civilian and military sites in the capital's Tajura district.
NATO warplanes have been raising the pace of their air strikes on Tripoli, with Gadhafi's Bab al-Aziziyah compound in the center of the city being hit repeatedly.
Journalists escorted into Bab Al-Aziziyah after Zuma arrived found a group of around 160 African visitors to Libya chanting pro-Gadhafi slogans and waving flags of nations including Chad, Niger and Ghana, in an apparent show of pan-African unity.
Britain said on Sunday it was to add "bunker-busting" bombs to the arsenal its warplanes are using over Libya, a weapon it said would send a message to Gadhafi that it was time to quit.
"Our operation in Libya is achieving its objectives ... We have seriously degraded Gadhafi's ability to kill his own people," NATO Secretary-General Anders Fogh Rasmussen told a NATO forum in Varna, Bulgaria.Story: Libya's Misrata rebels face tough new fight
"Gadhafi's reign of terror is coming to an end," he said.
Gadhafi denies attacking civilians, saying his forces were obliged to act to contain armed criminal gangs and al-Qaida militants. He says the NATO intervention is an act of colonial aggression aimed at grabbing Libya's plentiful oil reserves.
The Associated Press and Reuters contributed to this report.