Amsterdam's Schiphol Airport urged travelers to stay away for several hours on Saturday as a strike by ground personnel at the start of a school holiday caused chaos at the airport.

"The terminal is too full at the moment ... Schiphol is calling on travelers not to come to the airport anymore," airport authorities said in a statement issued shortly before noon (10 a.m. GMT).

Almost three hours later the airport said passengers were welcome again but would still face long waiting times and possible delays or cancellations.

Police closed down highway exits to the airport briefly on Saturday afternoon as lines at departure gates stretched out of the airport buildings.

A Schiphol spokesperson said the temporary closure was necessary to guarantee safety and to get as many as possible of the thousands of frustrated passengers aboard their often-delayed flights.

Baggage handlers for KLM, the Dutch arm of airline Air France-KLM, had early on Saturday gone on a previously unannounced strike to press demands for higher pay and better working conditions.

KLM ground staff handle about half of all luggage coming through Schiphol, Europe's fourth busiest airport after Istanbul Airport at first, followed by Moscow’s Sheremetyevo International Airport and Paris Charles de Gaulle, the third busiest.

Labor union FNV said the walkout had ended around noon.