Truck drivers are blocking more than 300 lorries from leaving Dublin Port in a protest over the Budget.
The Irish Road Haulage Association mounted the action early this morning, and is accusing politicians of not listening to members' concerns about their business costs, including the cost of road tax.
More than 150 people have joined the action outside the gates of Dublin Port, with no indication of when the protest will end.
Organisers say they are trying to avoid disrupting commuters, but there are some delays on the quays.
Dublin Traffic - avoid the area of Whitehall/ port tunnel. inbound traffic seek alternative route.
— An Garda Síochána (@GardaTraffic) October 20, 2014
The group's President, Eoin Gavin, said: "Currently it costs €4,000 to tax an articulated truck in the south of Ireland and ten miles over the border in the UK, it is £640.
"On top of that, the UK authorities have imposed a £10 charge per day, per truck, on all foreign vehicles entering the UK and Northern Ireland.
"It's unsustainable, the differential between operating a truck in the south of Ireland the north of Ireland is €5,000. It's unsustainable."
Traffic on East Wall Road is not understood to be affected so far, but AA Roadwatch is reporting that the Port Tunnel is closed.
DUBLIN: The Port Tunnel has closed due to a demonstration at Dublin Port. http://t.co/mnbPKwIPSi
— The AA Ireland (@aaroadwatch) October 20, 2014