In his testimony to the US Senate's Foreign Relations Committee, Olson stressed there had been significant progress in eliminating terrorist safe-havens due to Operation Zarb-e-Azb.
He added that Pakistan's leadership had assured commitment to completely eliminating terrorist safe-havens and US welcomed Pakistan Army Chief General Raheel Sharif's statement on July 6.
The special envoy said a constructive relationship between Afghanistan and Pakistan remained essential to bringing peace and stability to the region.
According to Olson, following significant improvement after the election of President Ashraf Ghani, relations between Afghanistan and Pakistan peaked and troughed over the past year in part due to critical issues, including refugees, border management, and counterterrorism. However, there have been some encouraging signs of progress in recent months.
After a meeting in June between Afghan Foreign Minister Rabbani and Pakistani Advisor on Foreign Affairs Sartaj Aziz, both sides agreed to coordinate at senior and tactical levels on border management issues; the first tactical-level meeting happened in late July and both sides agreed to meet again.
Olson further said the US supported this mechanism and believed that more bilateral dialogue between Afghanistan and Pakistan would increase prospects for mutual understanding, regional peace and stability.
In the wake of the deadly August 24 attack on the American University of Afghanistan in Kabul, Afghanistan provided Pakistan with evidence that prompted the Pakistan military to conduct combing operations in a few key areas along the Afghanistan-Pakistan border.
Pakistan is sharing the results of those operations with Afghanistan. Efforts to bring those behind the attack to justice are critical.
