Islamabad shut its Afghan border crossings to NATO supplies after US air strikes killed 24 soldiers last November, provoking the worst crisis in ties already frayed by the US raid that had killed Osama bin Laden in May.
But on Tuesday civilian and military leaders were to study reopening the route at a meeting of cabinet`s defence committee, with a meeting of army chiefs and the regular cabinet due on Wednesday, then a formal announcement.
Sources familiar with the discussions told AFP the government had effectively decided to end the blockade, probably by the beginning of next week, and expected to be invited to the May 20-21 NATO summit in Chicago.
Pakistani and US officials had reached a "broad agreement" on logistics for the fuel and other non-military supplies that would go overland through Pakistan to Afghanistan, one source said.
"The meetings will indicate that the decision has the backing of all the stakeholders," the source told AFP.
"This should minimise the prospect for Islamist groups to exploit the situation in the hope that they`ll get the backing of the military establishment."
Pakistan`s parliament has called in vain for an end to US drone strikes targeting Taliban and Al-Qaeda militants on its soil, and a formal US apology for the November air strikes.
But analysts say Islamabad has no choice but to reopen the border as US cash is needed to help boost its meagre state coffers, at a time when major NATO discussions are underway affecting its own strategic future.
Pakistan previously negotiated a fee of $160 per 40-foot container and is now looking to secure anywhere from $320 to $500, although the figure has yet to be agreed, one source told AFP.
The United States has also guaranteed payment of at least $1.1 billion should the borders reopen, as compensation for fighting militants in the northwest, the source added.
Foreign Minister Hina Rabbani Khar said on Monday that it was time to "move on".
"Pakistan has made a point and we now need to move on and go into a positive zone and try to conduct our relations," Khar told a news conference.
The cabinet`s defence committee, which includes the prime minister, army chief of staff and intelligence chief, was to convene from 1430 GMT.
Pakistan`s involvement in the Chicago summit would minimise its international isolation and could boost the country`s leverage over the future of Afghanistan, as NATO countries pull out their combat forces by 2014.
The US State Department said both countries had made "considerable progress" on ending the blockade, which has stopped fuel and supply trucks travelling from the port city of Karachi in the south to two Afghan border crossings.
State Department spokeswoman Victoria Nuland told reporters that discussions with Pakistan were "not yet finished".
"But we`re having a full review with the government of Pakistan on how this transit system works and all of the issues are on the table in that context," she said.
The US has made increasing use of more expensive routes into northern Afghanistan in its nearly 11-year fight against the Taliban and when they were cut as little as 25 percent of NATO`s needs travelled on the Pakistan channel.
Mir Mohammad Yousuf Shahwani, chairman of the All Pakistan Oil Tanker Owners Association, told AFP he had been informed by a senior official in the petroleum ministry that Islamabad would reopen the supply line within days.
"The petroleum official told me that they are finalising the details," he told AFP from Karachi. "Although we have concerns about security, we will start the supplies the moment they allow us."
But although Islamabad reiterated Monday that it would still like an apology for the November air strikes, the United States has expressed only regret for the deaths, which an American and NATO investigation said stemmed from mistakes made on both sides.