LONDON (Agencies) - Taliban chief Mullah Omar has given his approval for talks aimed at ending the war in Afghanistan and has allowed his representatives to attend Saudi-sponsored peace negotiations. "Mullah Omar has given the green light to talks," said one of the mediators, Abdullah Anas, a former friend of Osama bin Laden who used to fight in Afghanistan but now lives in London, according to The Sunday Times report. One of those negotiating for the Afghan government confirmed: "It's extremely sensitive but we have been in contact both with Mullah Omar's direct representatives and commanders from the front line." The breakthrough emerged after President Barack Obama admitted that US-led forces are not winning the war in Afghanistan and called for negotiations with "moderate Taliban". "A big, big step has happened," Anas said. "For the first time, there is a language of ... peace on both sides." A Sunday Times poll published Sunday found that 64pc of respondents favour talking to the Taliban to achieve a deal. Some 69pc said the aim of stabilising Afghanistan was not sufficiently worthwhile to risk the lives of British troops and 64pc thought the war could never be won. Although observers question why the Taliban would agree to talks when they appear to have the upper hand in the conflict, Anas said its leaders knew they could not retake power without a bloodbath. "Taliban are in a strong position now but that doesn't mean they can control the state," he said. "They are well aware that it's a different situation to 1996 when they swept to power because Afghans saw them as bringing peace." Britain is also backing talks with the Taliban that could lead to their inclusion in the Afghan government and is pushing for a "reconciliation czar" to coordinate efforts. "Economic development and a workable reconciliation strategy are as crucial as boots on the ground when it comes to dismantling the insurgency," said David Miliband, the foreign secretary. Meanwhile, a negotiator said Sunday that Taliban had shown optimism about holding talks with the Afghan government after calls from Washington to explore contacts with "moderate" militants. A Taliban spokesman nonetheless reiterated that the militant group would not enter negotiations unless international troops propping up the Kabul government pulled out of the country. Abdul Qayoum Karzai, the elder brother of President Hamid Karzai, who leads efforts on behalf of Kabul to persuade Taliban into talks, said President Barack Obama's recent statement had an "enormous effect". "It has created lots of optimism within the people of Afghanistan and also within the Taliban," he told AFP. "No other way is left but talks," Karzai added. He would not give details about the talks due to the sensitivity of the process that according to him has been ongoing for the "past two and a half years." "The former Bush administration's focus was only on military means and no place was left for talks," Karzai said. But "the people of Afghanistan, including the Taliban, believe that war is no way out of this situation in Afghanistan and we must talk," he said. Taliban spokesman Yousuf Ahmadi told AFP by telephone however: "We'll not talk to anybody unless the invading foreign forces leave Afghanistan." He had the same message in a round table discussion on private television late Saturday, in which he took part by phone, with two former members of the Taliban government also on the panel. Ahmadi also rejected a media report that the Taliban's elusive leader, Mullah Mohammad Omar, had given the green light to talks. "Such statements are baseless lies," he said. The Taliban were in government between 1996 and 2001. Their insurgency saw a record number of attacks last year with Kabul and its Western allies keen to break a stalemate in a dragging and deadly conflict, with consensus that victory does not lie in a military effort alone. Kabul has for years said it was willing to talk to Afghan Taliban who were not linked to Al-Qaeda and agreed to lay down their weapons and accept the democratic constitution.