Maritime union workers have begun major strike action over a pay dispute, disrupting shipping activity at Sydney, Melbourne and Brisbane.

Stevedoring company Patrick on Saturday said the action will affect 15 ships that are carrying about 17,800 containers.

The 24-hour industrial action will be followed with another strike scheduled on Monday at the Perth port of Fremantle.

Patrick director Paul Garaty said that while he was disappointed by action from the Maritime Union of Australia (MUA) the company remained willing to negotiate

"It's unfortunate that hundreds of Australian exporters and importers including small businesses waiting for deliveries will bear the brunt of the MUA's actions," Mr Garaty said in a statement.