A threatened strike at Dublin, Cork and Shannon airports has still not been called off, despite indications from SIPTU head office that it has not been sanctioned by them.

SIPTU's Civil Aviation Branch has served notice of industrial action from 4am to midday on Thursday in a dispute over non-payment of national wage increases, and increments.

The Dublin Airport Authority described the move as ‘totally unwarranted’, adding that a strike would disrupt thousands of passengers.

SIPTU members at the DAA engaged in several ballots for industrial action in recent weeks.

The main one was over participation in the proposed national strike this Monday - which has since been called off for national partnership talks to resume.

However, there was also another ballot on the local issue of the non-payment of increments.

It is understood that the Civil Aviation Branch accepted that the national wage issue would now be a matter for the partnership talks.

However, angry members have served notice of industrial action for next Thursday over the increments issue.

By last night, there was confusion about the validity of the notice of industrial action.

The DAA said that it had been served with notice regarding both the local and national issues - but SIPTU said it had only sanctioned Monday's now cancelled national strike.

The airport branch’s industrial action committee is said to be meeting on Monday.