Updated: 17.35

90,000 people have been affected by today's Luas strike so far, and Luas Drivers are adamant they won't be backing down in their pay demand.

Drivers are taking the action in support of a pay claim of over 20%.

No trams will operate until 5.30am on Friday morning, which is expected to increase pressure on other public transport services in the city.

Another strike is scheduled for next week.

Gerry Madden of Luas operator Transdev is urging the drivers to follow the example of other Luas staff - who have accepted a pay rise of 13%.

He says "it is the maximum that we can afford", although stressed that "there's always been this debate around what productivity the drivers can bring to the table.

"There's potential to be open-minded and reasonable if they can come and sell me something that I'd frankly want to buy," he added.

The latest strike action comes after the Luas operator said it will reduce drivers' wages by 10% from this Friday if their strike continues.

Transdev says it's an effort to recoup costs incurred as a result of the stoppages.

The union representing the drivers, SIPTU, says the reduction in pay would be illegal as its members are involved in a lawful industrial dispute with the company.

The union says the development will only serve to strengthen their resolve to continue their industrial action.

These drivers on the picket line aren't ruling out an all-out strike: