The incident comes a day after the Afghanistan government said it repelled a Taliban assault on the key border crossing with Pakistan amid the militants' sweeping advance.
Pakistan's Foreign Ministry confirmed on Thursday the Taliban were in control of a key town on the Afghan side of the strategic border crossing of Spin Boldak-Chaman, the latest in a series of key posts to come under their control in recent weeks.
"They have taken control of Spin Boldak border crossing," said ministry spokesperson Zahid Hafeez Chaudhri.
The Taliban announced they had taken the crossing on Wednesday, but the Afghan government later claimed to have retaken it.
The crossing is the second most important on the border with Pakistan and a major source of revenue for the Western-backed government in Kabul.
It provides direct access to Pakistan's Balochistan province, where the Taliban's top leadership has been based for decades. It also hosts an unknown number of reserve fighters who regularly enter Afghanistan to help bolster their ranks.
The Taliban continue to make strides in Afghanistan since US and NATO forces began their withdrawal from the country, 20 years after an invasion that was meant to prevent it from becoming a base for launching further terrorist attacks. At least 270,000 Afghans have fled their homes since the beginning of the year, according to a UN count.
Meanwhile, a high-level meeting began in the Uzbek capital of Tashkent on Thursday, gathering senior US, Russian and EU officials. The two-day regional meeting was originally supposed to deal with trade issues in South and Central Asia, but is now set to be dominated by discussions about the Taliban's advance in Afghanistan.
The meeting will include representatives of US Homeland Security as well as Washington’s special Afghan peace envoy, Zalmay Khalilzad. Also attending are Russian Foreign Minister Sergey Lavrov and European Union foreign policy chief Josep Borrell, as well as Afghan President Ashraf Ghani and Pakistani Prime Minister Imran Khan.