Pakistan Prime Minister Shaukat Aziz was in Afghanistan on Thursday for talks with President Hamid Karzai, an embassy official said amid a row over Pakistan's decision to fence and mine their joint border.
Aziz was due to go into talks with Karzai later on Thursday that the Pakistan foreign ministry said on Wednesday would "review all aspects of bilateral relations".
The discussions are expected to touch on Pakistan's announcement last month that it had tasked its army to work out logistical details for fencing and mining parts of the rugged 2,500-kilometre frontier.
That move comes after repeated accusations from Afghanistan that Pakistan is not doing enough to crack down on Taliban and other militants crossing from its side of the border to carry out attacks.
Karzai has said he would use "every method" to stop mines being planted on the border. The United Nations has also opposed the plan, with Afghanistan one of the most mined countries in the world after decades of war.
The leaders were also likely to talk about proposals for tribal council meetings on both sides of the border to tackle the unrest.
The neighbours have been at loggerheads about the dragging insurgency, which was its deadliest last year since the Taliban was toppled from government in late 2001.
Karzai in December publicly accused Islamabad of backing the Islamists, adding that Pakistan wanted to turn Afghans into "slaves".
Islamabad has denied the allegations and says it has 80,000 troops along the border to hunt down Taliban and Al-Qaeda militants.
Some 4,000 people -- including 1,000 civilians, but mostly rebels -- died last year in insurgency-related unrest.