US Army General David Petraeus is said to leave his post as the commander of the US and NATO forces in Afghanistan before the end of the year, a report says.

Petraeus, who was appointed less than eight months ago, will leave his post as the head of the US and NATO forces by the end of 2011 as part of a reshuffle plan that would see the departure of top five US diplomats in Kabul, including its Ambassador Karl Eikenberry, and Lieutenant-General David Rodriguez, deputy to Petraeus, the London-based Times reported Tuesday.

"General Petraeus is doing a brilliant job but he's been going virtually non-stop since 9/11 [and] he can't do it forever," Pentagon Secretary Geoff Morrell said. 

"This is a heck of a demanding job, he will have to be rotated out at some point," he further explained. 

With the administration of US President Barak Obama struggling to curb the nine-year old militancy in Afghanistan, the speculation has raised serious concerns over the fate of the prolonged war and the future war strategies in the war-wracked country. 

Sources have confirmed that the search for a new commander in Kabul is under way. 

The report further stated that Obama and the US Defense Secretary Robert Gates are already thinking about a candidate to take the job. 

The report has come to the fore a day after US Secretary of State Hillary Clinton chose retired diplomat Marc Grossman to replace the late Richard Holbrook as the US special envoy to Afghanistan and Pakistan. 

The moves also come against the backdrop of a sharp increase in the number of US fatalities in Afghanistan and plans to begin pulling US-led soldiers out of Afghanistan in July 2011. 

Some 150,000 NATO troops are currently fighting in war-torn Afghanistan, with plans to stay in the country even after 2014. 

In 2010, as many as 711 foreign troops lost their lives in Afghanistan -- an average of two a day -- which is by far greater than the annual toll of 521 during 2009. 

On December 16, Obama unveiled the result of a two-month National Security Council assessment on the war in Afghanistan, claiming that Washington has been "on track" in achieving its objectives in the war-hit country. 

Obama, however, warned that US-led troops in Afghanistan continue to face an uphill battle in their mission.source