Concerns are mounting at a controversial revision of Europe's air passenger rights, as crunch talks between European Parliament and Council negotiators are expected to continue next week ahead of a June 15th deadline.

Talks at the beginning of this week stalled over disagreement between EU governments and the European Parliament on the compensation passengers should receive in case of delayed or cancelled flights, as well as a proposed right to a carry-on luggage.

At present, passengers in Europe have a right to between €250-€600 in compensation, depending on flight distance, for delays of three hours or more.

Most EU governments agreed last year that the threshold should be extended to four hours for flights of up to 3,500 kilometres (2,175 miles) or for any flights within the bloc, and to six hours for longer journeys, with payout amounts between €300-€500.

The scheme also came with a "right to be rerouted" at the earliest opportunity and a system for passengers to be automatically compensated for flights cancelled within 14 days of departure.