Air travellers destined for Australia will face delays with border force and immigration officials resuming their airport strikes today.
The Community and Public Sector Union members have resumed rolling strikes at international airports around the country a week after industrial action planned for Easter was called off in the wake of the Brussels terror attacks.
Kiwi travellers had been warned to expect delays in the strikes.
Border Force officers are on strike and quarantine officers are imposing work bans, which is adding to delays.
Union national secretary Nadine Flood insists national security will not be jeopardised because officers involved had always been exempt from striking.
But Australia's immigration minister Peter Dutton is unconvinced.
"The threat hasn't passed within a couple of days following the Brussels attack," Mr Dutton told ABC Radio.
"These rolling strikes aren't welcome and I hope that they come to an end sooner than later."
Ms Flood said workers were striking as a last resort, as part of a two-year negotiating battle with the federal government over pay and work conditions.