"As of now Pakistan hosts three million Afghan refugees, and a large flow is likely to arrive", Khan said at the conference, adding that Pakistan had no economic capacity to accommodate more.
The prime minister added that Pakistan always stood against a military solution to the conflict in Afghanistan.
A two-day international conference dubbed "Central and South Asia: Regional Connectivity. Challenges and Opportunities" began in the Uzbek capital of Tashkent on Thursday. The conference is attended by Uzbek President Shavkat Mirziyoyev, Afghan President Ashraf Ghani, the Pakistani prime minister, EU foreign policy chief Josep Borrell, and Russian Foreign Minister Sergey Lavrov.
Violence has been on the rise in Afghanistan in recent weeks, as the Taliban* have intensified their offensive since the foreign forces began to withdraw from the country.
*The Taliban is a terrorist group banned in Russia.