Taiwanese airlines have rerouted flights as a result of the measure, data from the industry website Flightradar24 shows. So far, at least a dozen flights that would normally pass through Pakistani airspace have instead used Russian airspace - something they have avoided since Russia launched its full-scale invasion of Ukraine in 2022.
Pakistan's new stance is even tougher than China's, where Taiwan-based airlines can still use the country's airspace.
The "One China" policy means that Beijing claims Taiwan as part of China.
