Islamabad: After Pakistan cancelled the national carrier's flights between Islamabad and Kabul, a key route out of Taliban-controlled Afghanistan was cut off on Thursday.

Pakistan International Airlines (PIA), the national carrier of Pakistan, has accused the Taliban authorities of interfering with the flight operations by repeatedly changing regulations muddling permissions and limiting the number of people allowed on each flight, Washington Post reported.

The PIA on Thursday said it has immediately suspended its operation in Kabul citing "security reasons".

Abdullah Khan, the national carrier's spokesperson, confirmed the development, saying that Kabul operations of PIA will remain suspended until further notice, Dawn reported.

The spokesperson emphasised the fact that the PIA had kept flying in and out of Kabul under "difficult circumstances" when others had ceased their operations.

The suspension comes weeks after the Taliban promised to allow freedom of movement of all Afghans and restore regular international flights in and out of Kabul.

The Taliban took control of Kabul on August 15. The PIA was one of two international carriers that had kept their operations open at Kabul airport.

The other is Kam Air, a private Afghan airline with multiple flights a week to Islamabad.

Meanwhile, Qatar Airways also operates occasional flights between Kabul and Doha, Washington Post reported.

Khan said the decision to keep flying into Kabul had been a purely humanitarian one made "against all odds." He also said the high insurance rates required to land in Kabul made it difficult to keep the flights viable without increasing ticket prices.

Earlier on Thursday, The Afghanistan Civil Aviation Authority (ACAA) called on PIA and Kam Air airlines to bring down the fares of Kabul-Islamabad flights back to the pre-August 15 rates, Tolo News reported.

The ACAA also threatened to stop flights between Kabul and Islamabad if the airlines do not comply, Tolo News reported.

The disagreement between Pakistan and the Taliban over the flights also reflects the limitations of Pakistan's influence over the group, said Mosharraf Zaidi, a senior fellow at Islamabad-based think tank Tabadlab.

"At the end of the day, the ability of Pakistan to guide or direct the Taliban has a half-life that is very short and is diminishing fast," Zaidi said.