An advisory has been issued for all of New Zealand’s coastal regions after a powerful 8.8 magnitude earthquake struck off the east coast of Kamchatka, Russia.

Officials have warned that strong and unusual currents and unpredictable surges are expected to affect coastal areas across the country, posing a serious risk to anyone in or near the water.

The earthquake occurred at 11.25am New Zealand time, and authorities have since upgraded its magnitude to 8.8.

There are no changes to the areas under threat despite the upgrade, Civil Defence said.

Areas at risk include:

• All coastal areas of the North Island

• Great Barrier Island

• The South Island

• Stewart Island

• The Chatham Islands

Emergency authorities say people in or near the sea in these areas should immediately move out of the water, off beaches and shore areas, and stay away from harbours, marinas, rivers and estuaries.

“There is a danger to swimmers, surfers, people fishing, and anyone in or near the water close to shore,” the advisory said.

People on boats, live-aboards, or at marinas are advised to leave their vessels and head ashore. Officials are urging the public not to return to boats unless instructed to do so by emergency authorities.

Coastal flooding is not expected, and there is no need to evacuate other areas unless specifically directed by civil defence.

The first tsunami activity, causing these strong currents and surges, may reach areas around Lottin Point at approximately 11.59pm tonight. However, the threat may persist for several hours.

Authorities have stressed the following advice:

• Stay off beaches and shore areas

• Do not go to the coast to watch wave activity

• Follow instructions from local civil defence authorities