Air France managers have sent a letter to the airline's pilots calling for stricter observance of safety procedures, following a fatal crash in June, French newspaper La Tribune reported.

The paper said Air France management was responding to pressure from pilots' unions to reform security regulations following the crash of flight AF447 en route from Rio de Janeiro to Paris in June, which killed 228 people.

The paper said head of air operations Pierre-Marie Gautron and head of safety Etienne Lichtenberger wrote to all of the airline's pilots, drawing attention to recent major incidents that took place because some pilots did not respect flight procedures.

The examples given included a flight taking off despite an alarm sounding during take-off, and incorrect refueling, La Tribune said.

"The simple application of procedure would have meant these events could have been avoided. We do not need to modify procedures or create new ones," they said in the letter quoted by La Tribune.

An Air France spokeswoman acknowledged the existence of the letter but declined to comment further.