Pakistan has categorically rejected reports of the Washington Times about presence of Afgan Taliban leader, Mulla Mohammad Omar, in Karachi of the country.

Speaking to a private Pakistani TV channel, Pakistan's Foreign Office spokesman, Abdul Basit, stressed that Omar was not present in Karachi.

The spokesman also denied Pakistan intelligence service ISI's involvement in shifting Mulla Omar to Karachi, saying that the Washington Times report was part of international propaganda against Pakistan.

Washington Times report has claimed that Mulla Muhammad Omar had fled Quetta and found refuge from potential US attacks in Karachi with the assistance of the Pakistani intelligence.

Two senior US intelligence officials told the newspaper that Mulla Omar travelled to Karachi last month after the end of Muslim holy month Ramazan, adding that the fugitive Afghan insurgent leader also inaugurated a new senior leadership council in Karachi.

The officials accused the ISI of helping the Taliban leaders move from Quetta, where they were exposed to attacks by the US drones.

Bruce Riedel, a CIA veteran and analyst on al-Qaida and the Taliban, alleged that Mulla Omar had been spotted in Karachi recently.

"There are indications of some kind of bleed-out of Taliban types from Quetta to Karachi, but no one should assume at this point that the entire Afghan Taliban leadership has packed up its bags and headed for another Pakistani city," Riedel said.

Talking to CIA Director-General Leon Panetta in Islamabad on Friday, President Asif Ali Zardari claimed that al-Qaida and the Taliban leaders were not present in Pakistan, adding that the US leadership must share all kinds of information with Pakistan because the war on terror "was not our war only."

Similarly, Ahmad Shuja Pasha, the ISI chief, while talking to Panetta, recorded his strong protest on linking his organization with Taliban, terming the Washington Times report "fabricated and baseless".

To further stoke the fire, the US-based Rantburg.com website on Saturday said in a report: "The United States has come perilously close to calling Pakistan a terrorist state by alleging that the country's spy agency ISI recently spirited Taliban leader Mullah Omar to Karachi to save him from American drone attacks in Quetta."

"The latest US charges recalled one of the biggest scandals of the Bush administration's War on Terror, when Washington allowed a secret airlift by Pakistan of hundreds of its military and intelligence personnel trapped in Kunduz, Afghanistan, where they were helping the Taliban against US," the report said.

It added that in his book, Descent into Chaos, Pakistani journalist, Ahmed Rashid says hundreds, perhaps as many as 1,000 ISI officers, Taliban commanders, and foot soldiers belonging to the IMU (Islamic Movement of Uzbekistan) and al-Qaida personnel boarded the planes.

Frustrated US Special Ops Forces who watched it from the surrounding high ground dubbed it "Operation Evil Airlift," the website quoted Ahmad Rashid as saying.

Reports say the CIA chief raised the issue of Mulla Omar presence with the ISI chief, Lieutenant General Ahmed Shuja Pasha, who categorically denied presence of the Afghan Taliban chief in Pakistan.

On Friday, a Pakistani news website, Pakistandefence.com quoted the country's Aaj television network as reporting that Pasha, rather, presented evidence of CIA involvement in the country to Leon Panetta.

These reports and the charges attributed to both sides reveal that relations between the United States and Pakistan have once again hit snags and may face further difficulties if instant remedial steps are not taken.