South African President Jacob Zuma is in Libya's capital, Tripoli, for talks with Col Muammar Gaddafi to seek a diplomatic solution to the conflict. A spokesman said his main objective was a ceasefire and denied he would discuss exit strategies with the Libyan leader. One of Col Gaddafi's advisers has told the BBC there is no prospect of him stepping down, as the rebels demand. On Sunday, Mr Zuma's governing African National Congress condemned Nato's air and missile strikes in Libya. "We... join the continent and all peace-loving people of the world in condemning the continuing aerial bombardments of Libya by Western forces," the party said after a two-day meeting of its executive council. Nato imposed a no-fly zone in Libya and began bombing Col Gaddafi's forces in March as they threatened to overrun rebel-held parts of the country, a month after nationwide anti-government protests began. International pressure on Col Gaddafi continues to grow, with the G8 calling for his departure on Friday and Russian President Dmitry Medvedev saying on Saturday he no longer had the right to lead Libya. The chairman of the Benghazi-based rebel Transitional National Council (TNC), Mustafa Abdul Jalil, welcomed the statements, saying: "The entire world has reached a consensus that Col Gaddafi and his regime have not only lost their legitimacy but also their credibility." But the Libyan government said it was not concerned by the G8's decisions, saying it was merely an economic summit. "We are an African country. Any initiative outside the AU framework will be rejected," Deputy Foreign Minister Khalid Kaim said. Attack helicopters Mr Zuma walked down the red carpet at Tripoli's airport on Monday afternoon to the sound of a band and children waving Libyan flags and chanting "We want Gaddafi" in English, the Reuters news agency reports. Col Gaddafi - who was last seen on state television meeting tribal leaders on 11 May - was not among the dignitaries who greeted him. The president was later taken to Col Gaddafi's house in the Gargour area of Tripoli, where Libyan officials said his son Saif al-Arab was killed in a Nato strike in late April, and also the Bab al-Aziziya compound. Mr Zuma's office said the main objective of his visit was to discuss with Col Gaddafi an immediate ceasefire, the delivery of humanitarian aid and the implementation of reforms needed to end the crisis. It also rejected as "misleading" reports that their talks would focus on agreeing an exit strategy for Col Gaddafi. South Africa voted for the UN Security Council resolution authorising the use of force to protect civilians in Libya despite the AU's concerns. Since then, Mr Zuma has joined other African leaders in accusing Nato of overstepping its mandate and calling for an end to the bombardment. The BBC's Andrew North in Tripoli says some hope Mr Zuma's charm and personal relationship with Col Gaddafi will make a deal possible. But the prospects for this peacemaking bid look just as thin as last time, our correspondent says. An African Union "roadmap", which was drawn up in February and called for an immediate ceasefire, was swiftly rejected by both the TNC and Nato because it did not call on Col Gaddafi to step down. His supporters insist there is no possibility of him either leaving office or Libya, and point out that even if he did he could then face being arrested and taken to the International Criminal Court at The Hague on war crimes charges, our correspondent adds. On Saturday evening, Mr Abdul Jalil reiterated the TNC's stance and accused government forces of attacking rebel-held towns in the western Nafusa mountains "with heavy artillery, tanks and rocket launchers" and continuing to besiege the rebel-held city of Misrata. "We witness how Col Gaddafi presents initiatives to fool the world and create the illusion that he is in search of peace," he said. "It is with this in mind that we would like to reconfirm that the basis of any consideration for the resolution of the Libyan crisis is the removal of the main reason for this crisis, Col Gaddafi. As such, there is no room for negotiation until his departure and the departure of his regime." On Monday, rebel spokesman Guma al-Gamati told the BBC World Service that he believed Mr Zuma's visit would make a difference as Col Gaddafi was far weaker and more isolated than he was last month. "The people around him and the aides and people who are fighting for him are diminishing; some are deserting," he added. Nato Secretary General Anders Fogh Rasmussen echoed the comments, telling a meeting of the alliance's parliamentary assembly: "Gaddafi's reign of terror is coming to an end. He is increasingly isolated at home and abroad. Even those closest to him are departing, defecting or deserting." Mr Zuma's visit comes days after the UK and France announced they were sending attack helicopters to join the Nato effort, as the alliance attempts to break the deadlock which has left the rebels in control of eastern Libya and the government running most of the west. The UK also said it could start using "bunker-busting" Paveway III bombs, capable of penetrating reinforced buildings. Libyan state media said on Monday that Nato aircraft had killed 11 people at civilian and military sites in Zlitan, 50km (30 miles) west of Misrata. Al-Arabiya meanwhile reported that a group of 120 Libyan army officers had defected and travelled to Rome. A rebel leader told the AFP news agency that eight senior officers, including four generals, were among them and would shortly address the media in Rome. Source: BBC