South African Airways (SAA) has said it does not have money to pay its employees their May salaries.
About 5,000 employees have been on unpaid leave since the beginning of May.
The only money employees can expect to receive this month is from the unemployment insurance fund, the aviation organiser at the Solidarity trade union, Derek Mans, is quoted by Reuters news agency as saying.
The team rescuing the struggling airline originally wanted to dismiss the 5,000 staff.
That was stopped by the labour court but they have now been allowed to appeal that ruling, according to the Independent Online website.