PARIS, July 3 (Xinhua) -- French Civil Aviation Authority on Tuesday asked airlines to cancel 40 percent of flights at Paris airports on Thursday due to an air traffic controllers' strike, with southern regions already experiencing severe disruptions on the eve of summer school holidays.

Air traffic disturbances stemming from the strike on Thursday and Friday are not isolated to Paris. The Directorate General for Civil Aviation (DGAC) reported widespread impacts extending to multiple other French cities.

In addition to the significant impact on Paris airports, half of the flights at the airport in Nice, the third largest in France, will be canceled.

The DGAC, seeking to align controller staffing with flight volumes to prevent further disruptions, has ordered 30 percent flight cancellations at airports in Lyon, Marseille, Montpellier, Ajaccio and Figari, according to a press release.

"Despite preventive measures, significant disruptions and delays are expected nationwide," the DGAC warned, noting that controllers' chronic understaffing has critically impacted operations.

The strike, led by the second-largest union UNSA-ICNA and the third-ranked USAC-CGT in France, follows failed negotiations over working conditions. Unions specifically denounce structural understaffing, mismanaged technical projects, and what they term as "toxic management" within the DGAC. The largest union, SNCTA, however, declined to join the strike. ■