What is the Durand Line? The disputed border fueling Afghanistan–Pakistan conflicts

Pakistan’s Defence Minister Khawaja Asif announced on Friday that Pakistan and Afghanistan are now in “open war”. Islamabad has also carried out airstrikes on Kabul and other cities along the border. Meanwhile, Taliban government spokesperson Zabihullah ⁠Mujahid also said earlier that Kabul was launching “large-scale offensive operations” against the Pakistani military along the Durand Line, which separates the two countries.

Tension between Afghanistan and Pakistan escalated to the next level after both countries clashed in October 2025, killing dozens of soldiers, civilians and suspected militants. Hostilities have been taking place between Pakistan and Afghanistan ever since the Taliban authorities returned to power in 2021.

When Afghanistan's new government assumed power, it declined to formally recognise the border with Pakistan, arguing that the line was imposed during the colonial era, which unfairly divided ethnic Pashtun areas between the two countries. The boundary, known as the Durand Line, stretches 2,611km (1,622 miles) between Afghanistan and Pakistan.

What is the Durand Line?

Central to the dispute is the 2,611-km frontier drawn in the 19th century during British colonial rule. The line is named after Mortimer Durand, the British official who negotiated the agreement with Afghan ruler Abdur Rahman Khan. It cuts through ethnic Pashtun territories, a division that has long fueled political and nationalist tensions.

In 1893, British India and Afghanistan signed an accord defining their respective spheres of influence, resulting in the demarcation of the line. This agreement divided the Pashtun tribal areas, leaving communities on both sides of the border. After Pakistan was established in 1947, it inherited the Durand Line as its western boundary. While Pakistan regards it as the legitimate international border, successive Afghan governments have declined to formally accept it.

Afghanistan has continuously challenged the legitimacy of the Durand Line, arguing that the original agreement was made under British coercion and should not automatically bind Pakistan as a successor state.