A fresh strike by Ryanair air crew in Belgium will result in 152 flight cancellations this weekend at the country's second airport, Charleroi, the airport boss told AFP on Friday.

The stoppage by the 400 flight attendants based in Belgium for the Irish low-cost carrier - the biggest in Europe in terms of passengers transported - follows on from one over the New Year last weekend.

That caused around a hundred flight cancellations at Charleroi, which Ryanair uses at its main hub in the country.

The fresh strike on Saturday and Sunday is expected to lead to 76 outgoing and 76 incoming flights being cancelled, affected "some 20,000 passengers", Charleroi airport boss Philippe Verdonck said.

He said all those affected passengers had been notified by Ryanair.

The airline runs 15 aircraft out of Belgium, and the strike was only to affect those planes, and not ones it operates out of other European countries.

The head of the CNE union covering Ryanair staff, Didier Lebbe, said the employees would gather early on Saturday at Charleroi airport.

Ryanair employees staged several strikes in 2022. 

They notably accuse the airline of illegally pressuring some of them to fill in at bases in other European countries, especially in Dublin.

And they allege Ryanair is not correctly declaring them in the Belgian social security system and sometimes pays wages below the national legal minimum.

Ryanair on Wednesday said it forecast a higher post-tax profit for the fiscal year ending March 31, citing stronger-than-expected travel demand and revenues over the end-of-year holiday period.