WELLINGTON, May 16 (Xinhua) -- New Zealand has become the first country in the world to roll out nationwide biofouling rules to stop dirty vessels from contaminating the country's waters, Minister of Biosecurity Damien O'Connor said on Wednesday.

"About 90 percent of non-indigenous marine species in New Zealand, such as Mediterranean fan worm, Japanese kelp and Australian droplet tunicate, arrived on international vessels. These incursions harm our aquaculture industries, fisheries and native marine ecosystems," O'Connor said in a statement.

Under the new biofouling rules, operators must prove they've taken appropriate steps to ensure international vessels arrive with a clean hull, he said, adding that the new rules will better protect New Zealand's unique marine environment and other vital industries from biosecurity risk.

"Biosecurity New Zealand officers will take a hard line on vessels that can't provide evidence they meet the rules. Divers will carry out inspections of hulls," O'Connor said, adding that officers will also have the power to direct vessels for cleaning and order the vessel to leave New Zealand if the fouling is severe.

The definition of a clean hull will depend on vessel type and its itinerary, the minister noted, adding the rules are stricter for vessels that are staying in New Zealand for a long time with the intention of visiting a range of ports.