Air France-KLM’s low-cost carrier Transavia is at risk of walkouts by cabin crew this summer even after agreeing to pay bonuses to staff in a bid to maintain labor peace.

One of the carrier’s flight attendants’ unions, SNPNC, has issued a strike warning that runs through mid-September, without yet giving any specific dates, according to spokesman Lionel Trovao.

The union refused to sign a labor agreement reached last week with other groups including the biggest CGT union because the accord included bonuses but no increases in base pay, which is below minimum wage for new cabin-crew hires, he said.

The labor agreement included special payouts and improved staff scheduling, a spokesman for the airline said, adding that when variable portions are added to base pay, compensation is above minimum wage. 

Air France-KLM’s decision to grant extra compensation to Transavia staff in a bid to avert strikes comes amid travel disruptions across Europe. SAS AB, Ryanair Holdings Plc and EasyJet Plc have faced strikes while British Airways agreed to settle a dispute with check-in workers. 

Any significant labor action at Transavia would shatter one of the achievements most vaunted by Air France-KLM Chief Executive Officer Ben Smith. He took the helm in 2018 following a period of crippling Air France strikes, and has said the labor peace that has followed is crucial for the turnaround of the embattled carrier.