MANILA (AFP) - Budget Philippine carrier Zest Air was banned from flying over safety infractions, effective immediately, the country's aviation regulator said on Friday.

The small airline is suspended over incidents that compromised several flights as well as other violations of air safety rules, Civil Aviation Authority of the Philippines deputy director-general John Andrews said in a letter to operator Zest Airways Inc.

"(Your) Air Operator Certificate is suspended and (you are) hereby precluded to engage in air carrier operations ... until this Authority is assured that the necessary corrective actions and compliance with aviation safety standards have been undertaken," Mr Andrews said.

Five Zest Air domestic flights were grounded between July 22 and August 13 due to problems ranging from hydraulic systems issues, fuel overflow, and a missing fuel coupling cap, Mr Andrews said.

A Zest Air plane was also found refuelling on Wednesday while its passengers were on board, he added.

Zest Air pilots, meanwhile, were found to have exceeded the flying time limit of 100 hours per month "due to (a) rise in flight operations and flight crew shortage".

Twenty-four of its pilots exceeded the monthly limit last year, Mr Andrews said.

Zest Air had also failed to appoint an "accountable manager" after the resignation of its previous executive on July 19.

Mr Andrews said the manager is responsible for "ensuring that all flight operations and maintenance activities can be financed and carried out to the highest degree of safety standards".

Zest Air, which operates out of Manila airport, serves the domestic market.

Malaysia-based Air Asia, South-east Asia's biggest budget carrier, bought a 49 per cent stake in Zest Airways in March.