More than 1,500 flights have been cancelled on July 3-4, affecting nearly 300,000 passengers, due to a strike by French air traffic controllers, European industry lobby Airlines for Europe said in a statement.

Airlines and France's transport minister has condemned the strikes as unacceptable, at the start of summer holidays.

Tens of thousands of passengers across Europe have been affected as French air traffic controllers began a two-day strike at the start of a busy summer holiday season to protest against understaffing and “toxic management”.