SIPTU insists Luas drivers have their backing if they decide to escalate their pay dispute.

Yesterday saw thousands of commuters forced to take alternative routes to work as workers downed tools in the 12th day of strike action.

The Labour Court will meet with both sides in the long running row next week - to decide if it should intervene.

Luas shop steward Richard McCarthy members would ballot on an all-out strike in the next two weeks, as a 'defence' against any 'attacks' from tram operator Transdev.

Siptu, though, have said that a decision on whether to ballot for an all-out strike has yet to be taken.

Sipty's Owen Reidy says his members are resolute, and say he would welcome any intervention.

"They are obviously annoyed with the employers' behaviour to date, but they are resolute in seeking a fair settlement.

"They, like we, would welcome any potential intervention, were it forthcoming."