The number of passengers at the airport will be limited until mid-September due to staff shortages.

In an open letter to passengers, John Holland- Kaye called on airlines to stop selling new tickets as critical functions in the airport have been constrained.

Some summer journeys will be moved to another day, another airport or be canceled, and we apologize to those whose travel plans are affected. He said there have been times when service had dropped to a level that was not acceptable.

According to Mr. Holland- Kaye, the airport could only handle 100,000 departures a day, slightly less than the 104,000 he estimated would be served. The cap on the number of tickets airlines can sell was 100,000.

Hannah Smith, a spokeswoman for the airport, said that the capacity limit would be enforced by an independent coordinating body. She said that airlines have the ability to apply limits to their schedules.

Summer travel in Europe has been marred by chaos at airports as airlines have struggled to keep up with surging numbers of passengers, eager to travel after the swine flu scare. SAS filed for Chapter 11 protection after its pilots went on strike. Airport and airline staff in Europe have walked off the job in protest of long hours and low pay that has not kept up with inflation.

Measures have been introduced at other airports. Last month, Schiphol Airport in Amsterdam introduced a capacity cap due to a shortage of security employees and demand for air travel far exceeding expectations, and London's Gatwick Airport also said it would reduce flights for July and August. British Airways will operate on a reduced schedule through October.

In anticipation of high demand for summer travel, Mr. Holland- Kaye said that he had started recruiting in November, but that some key roles were still understaffed.