Airline passengers have been warned to expect delays after public sector workers resume industrial action at international airports on Wednesday.

The Community and Public Sector Union is taking the action after postponing planned Easter strikes in the wake of the terror attacks in Brussels.

The action by Immigration and Border Force employees and union members employed in Agriculture and Water Resources will include "short rolling strikes" at international airports.

International airline passengers could face delays. Kate Geraghty

The union said passengers might experience some delays when departing or arriving on international flights.

CPSU national secretary Nadine Flood said the action would not compromise national security.