Signaling a slight improvement in the diplomatic ties between Washington and Islamabad, the US military has returned two officers to the headquarters of the Pakistani army's 11th Corps to help coordinate military actions along the Afghan border.

The officers were sent last month to Peshawar, close to the Afghan border, after months of severed ties following a US drone attack on a Pakistani site in November which killed 24 Pakistani army personnel. The US withdrew its military liaison officers and trainers following the fallout while Pakistan shut down all the NATO supply routes to Afghanistan in protest against the aerial strike.

Pentagon spokesman Navy Capt. John Kirby said Thursday that Pakistan had not reached an agreement yet to reopen land routes into Afghanistan, the blockade of which has been creating problems for the 140,000 foreign troops and Afghan citizens in the war-shattered zones, according to an Associated Press report.

As a rapprochement gesture ahead of the NATO summit last month, Pakistan said on May 15 that it was considering reopening its Afghan border to NATO supply troops. However, US President Barack Obama snubbed Pakistan in his remarks at the summit, by leaving it off the list of nations he thanked for getting war supplies into Afghanistan.

Pakistan risks domestic protest by ending the blockade since the US never apologized for the attack, maintaining that it was an accident.

The newly-returned liaison officers would seek to foster communications between the foreign troops in Afghanistan and Pakistani soldiers as NATO struggles to contain the militants waging a battle against the Taliban.

Though the reinstating of the military officers is not seen as critically important, a US official on condition of anonymity said, It's not insignificant that this is happening.

However, the situation remains tense between both the nations, as Pakistani officials refuse to ease restrictions on issuing visas to the US intelligence personnel, Reuters has reported. At a strategic level, the relationship is still at a very rough place, the official was quoted as saying.

There's a lot more we want to do to improve it, but (the military officials' return) is an important sign that at least in some areas we're getting a healthy sense of normalcy.

Meanwhile, the Pakistani military denied Thursday an earlier report which had said that the US had returned military trainers to a training site in the northwestern Pakistan. Pakistan had shut down the training program following the controversial attack.