Sweden said Sunday it would bar entry from Norway for three weeks, after a cluster of a faster-spreading coronavirus strain appeared in its neighbour's capital Oslo.
"Since Norwegian shops and alcohol stores are closed, there is a risk that Norwegians come to Sweden and contribute to infections," Interior Minister Mikael Damberg told reporters.
People who live and work in Sweden will be exempt from the entry ban, set to come into force from midnight on Monday.
Meanwhile Stockholm said that it would extend a similar ban on arrivals from Britain, where the faster-spreading variant was first detected, and neighbouring Denmark over the same period, until February 14.
By Wednesday, Sweden had already detected 50 cases of the British variant, while Norway's count was up to 70 by Sunday.
Oslo and the surrounding region are under Norway's toughest lockdown measures since the start of the coronavirus pandemic following the detection of variant cases just outside the capital.
Norway has further tightened its own entry rules, demanding arrivals present a negative PCR test from within the past 24 hours and requiring additional tests for those travelling from areas at risk of the new variants.