In a direct repudiation of repeated claims of Pakistan, a top American general based in Afghanistan has said that reclusive Taliban leader Mullah Omar is hiding in Pakistan along with his commanders.

The statement contradicts Islamabad's stand that the Taliban leader lives across the border in his own country.

"Omar lives in Pakistan, as do many of his commanders. From that safe vantage point, they've sent hundreds of young, impressionable, largely spiritual and helpless youths to their deaths and detention in Afghanistan. For this, they must forfeit their honor and any claim to Islamic virtue," General John Allen, Commander of US and Nato forces in Afghanistan, wrote in an article in The Washington Post.

Allen's article focused on the recent increase in attack on US troops from the Afghan security force, which the Taliban has been claiming it has infiltrated and carrying out such attacks.

"The focus on 'green-on-blue' attacks obscures the callous slaughter of Afghan civilians by insurgents led by Mohammad Omar. He has the blood of innocents on his hands even though he hypocritically tells his subordinates not to attack civilians," Allen said, holding that Omar is either out of touch, or his forces are out of control.

"Perhaps that should be no surprise. 'Green' and 'blue' have been taking the fight to the red enemy, the Taliban, and the enemy is fighting back from a position of weakness," said the top American commander, holding that the outfit has been losing ground.

"His forces have largely been ejected from most of the relevant population areas, and from among the most relevant terrain in Afghanistan. Omar is losing financial support from donors, who are sending their money elsewhere, and from reduced drug profits, thanks to Afghan and coalition efforts to stamp out the poppy harvest," he said.

Allen also appreciated Afghan security forces for their efforts in curbing Taliban's influence.

"Finally, Afghan security forces are increasing in number and quality every day. The area controlled by allied and Afghan forces reaches into Taliban support zones that had long been inaccessible," he said.

Holding that Islam never permits acts like "murdering innocent civilians" and the "scourge of drugs and abject criminality", the official said with every act of violence and atrocity on innocent Afghans, the insurgents were only distancing themselves further from Afghan people.

Meanwhile, the US has warned its citizens of travelling to Pakistan in the wake of possible terror threats in the country.

Urging American nationals to avoid protests and large gathering, the State Department, in a travel advisory, said that the presence of al Qaeda, Taliban elements, and indigenous militant sectarian groups poses a potential danger to US citizens throughout Pakistan.

"Threat reporting indicates terrorist groups continue to seek opportunities to attack locations where US citizens and Westerners are known to congregate or visit, such as shopping areas, hotels, clubs and restaurants, places of worship, schools, and outdoor recreation events," it said.

Travel to much of Khyber Pakhtunkhwa Province and Balochistan was also restricted as per the new advisory that replaces the one issued earlier on February 2.

It also "strongly urged" the US citizens to avoid hotels that do not apply "stringent security measures" and asked them to maintain good situational awareness, particularly when visiting locations "frequented by Westerners."

"Since the announcement that Osama bin Laden was killed in Abbottabad, Pakistan on May 2, 2011, US citizens should be aware of the possible increase in the threat level throughout the country. This might include an increased threat against Westerners," the advisory said.

Due to security concerns, the US government currently allows only essential travel within the FATA by US officials.