Pakistan International Airlines (PIA) has been forced to ground all flights for a second consecutive day following a strike by staff.

Workers at the airline walked out on Tuesday, with the carrier battling to keep a number of flights operating.

However, picket lines have continues to grow, with PIA today forced to cancel around 250 flights.

Up to 45,000 passengers have been impacted by the dispute, with the airline losing around $19 million for each day of action.

PIA is already on the verge of bankruptcy, with plans to subcontract routes in the European Union and United States to Turkish Airlines in order to cut costs at the centre of the latest dispute.

Protests want the plan scrapped and the managing director sacked.

Two rounds of crisis talks between union leaders and government representatives have ended without any breakthrough.

“Like yesterday, we have total shutdown today. We had to cancel about 120 flights on Thursday and as many today,” PIA spokesman Mashhood Tajwar told AFP.

The airline provides the only direct service from Pakistan to Britain, Europe and North America.