A climate change protest off the coast of Australia's New South Wales State forced an inbound ship to turn back from the country's largest terminal for coal exports on Sunday, the port operator said.

Port operators said they expected to maintain normal operations if police were able to manage the demonstrators.

Australian police said they arrested three climate change activists on Saturday when protesters tried to disrupt the movement of vessels at the country's biggest coal port. Protest organiser Rising Tide said hundreds of activists were in the harbour near the Port of Newcastle,

Protesters risked arrest and paddled out into a channel at the Newcastle Port to stop a coal ship from leaving.