The action was carried out by Extinction Rebellion, who have called for an end to the highly polluting vessels in the Dutch capital.

"Oil kills, stop cruise ships", the activists spray-painted on the doors of the lock they had tied themselves to, according to footage broadcast live online on their video stream, XRTV.

Carlijn van Essen, a spokeswoman for the Port of Amsterdam, told AFP that the activists were at two locks in the huge IJmuiden complex, northwest of the capital.

The action is blocking the passage of the "Serenade of the Seas" cruise ship with a thousand cabins, which was en route to Amsterdam, she said. An oil tanker was also blocked.

A week ago, 2,000 passengers from a cruise ship had to be evacuated by bus after similar action, Dutch public media NOS reported.

Extinction Rebellion became notorious for direct action protests such as shutting down bridges over the Thames river in London, but has largely shifted focus from mass civil disobedience to building an inclusive grassroots movement.

According to a study by the NGO Transport and Environment, cruise ships sailing in European waters in 2022 emitted more than eight million tonnes of CO2 -- the equivalent of 50,000 Paris to New York flights.

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NOS