An earthquake of 6.2 magnitude jolted the sparsely populated Svalbard archipelago in the Arctic last night.
The Norsar seismic research institute said it was the biggest earthquake on Norwegian territory in history.
No one was hurt by the quake and no damage has been reported in the islands, about 1,000km from the North Pole.
The earthquake happened at sea about 10km below the surface, and was felt strongly in Longyearbyen.
Norwegian Prime Minister Jens Stoltenberg, European Commission President Jose Manuel Barroso and other leaders will be in Svalbard next week.
They are due to attend the official opening of a seed vault which will store frozen crop seeds from around the world in case crops are wiped out by a future disaster.
It may take a few days for aftershocks to stop but that they should not pose any risk to next week's ceremonies.
