Trade union the National Transport Movement has threatened to shut down South African Airways after the embattled state airline announced that it would undergo restructuring.On Monday, the airline said it has started a restructuring process that could see its workforce cut by almost a fifth.As required by South African law, the carrier has started talks with labour unions about its plans, which could affect 944 of its 5,149 employees, SAA said in an emailed statement.President of the National Transport Movement Mashudu Raphetha said that the retrenchments were anticipated and that his union’s membership was taking a ballot on whether to embark on strike action.He added that his union has reached out to sister organisations such as Numsa to also engage in the industrial action.“It is time now to unite and we are going to shutdown. We have been trying to engage with the company but it is not (being reasonable) and is not listening to us.“Our doors are open and we are still open to persuasion, but if they continue like this then our members will push us to ensure that we have a total shutdown of SAA”.The proposed restructuring includes all SAA divisions and departments, excluding its Mango Airlines, Air Chefs and SAA Technical units, it said.SAA has incurred more than R28 billion in cumulative losses over the last 13 years and missed the deadline to submit its earnings for the financial year ending March.While it recently received a R5.5 billion lifeline to extend maturities on outstanding debt, it hasn’t been able to reach an affordable repayment plan with creditors.