KARACHI Pakistan State Oil (PSO) has cut 40 per cent oil supply to PIA over the non-payment of Rs 2 billion dues, leading to delays and cancellation of 11 flights in a day on Thursday. Sources privy to the matter disclosed that as many as 11 national and international flights have been cancelled in one day, indicating a serious mismanagement in the organisation. The flights which were unable to fly as per schedule and cancelled included London-Karachi PK 788, Sialkot-Karachi PK 397, Turbat-Karachi PK 154, Sehwan ShareefKarachi PK 367, Islamabad-Karachi PK 579, Multan-Karachi PK 521, Karachi-Turbat PK 153, Karachi-Sehwan Shareef PK 578, Karachi-Multan PK 874, Karachi-Colombo PK 233, Karachi-Muscat PK 234, Muscat-Karachi PK 875. On the other side, six flights of PIA were delayed by 2-5 hours at Karachi Airport. Sources disclosed various reasons behind the crisis as Haj operations require strength of planes and fuel. They also said that several domestic and international flights of PIA faced massive disruptions across the country due to shortage of aircrafts and pilots also. Hundreds of passengers have been stranded at major airports across the country. However, authorities claimed that the passengers of the cancelled flights will be adjusted in other flights. PIA departmental sources said that the Pakistan State Oil (PSO) has reduced the level of supply to PIA which is main reason behind the crisis. Spokesperson of Pakistan State Oil Mariam Shah declined the cut of 40 per cent by PSO but said that PIA deserved the cut because of the non-payment of rupees two billion. Spokesman of PIA Tajwar when contacted held weather responsible for delay and cancellation of flights. In reply, he said that PIA has credit limit of Rs one billion and it does not usually exceed. He said all the flights of PIA were being run normally from Karachi Airport.