Air Canada said its operations returned to normal on Monday after 4 percent of flights were canceled on Sunday.

The airline said on Sunday that it canceled about 4 percent of scheduled flights because certain pilots had reached their flying time quota for the month.

A spokeswoman for the airline could not provide details on the number of flights canceled or passengers affected.

Air Canada said the percentage of flights affected represented less than the number typically canceled on a bad weather day, and were limited to the airline's narrow-body Airbus fleet.

A disruption of flight operations at Halifax Airport in July and bad weather in the northeast United States and central Canada also produced a number of canceled flights during the month.

That led to flight diversions and the use of a significant number of flying hours not previously planned, Air Canada said.

The airline said it began adjusting schedules two weeks ago, canceling some flights and adding others with larger aircraft, almost exclusively on high-frequency routes on Canada and to the United States.