Speaking to reporters in Germany, where the far-right Alternative für Deutschland (AfD) could come top in three state elections next month, Starmer said the increase in support for such groups was "something that occupies my time".
His words came just weeks after UK riots partly inspired by far-right misinformation.
"I do think that we should be alive in the UK to the challenge of the far right and populism and nationalism," the prime minister said after talks in Berlin with Olaf Scholz, the German chancellor.
"There are a number of reasons for my concern: partly what's happening in the UK, partly what you can see happening in other European countries, including in France and in Germany.
Denne historien er fra August 29, 2024-utgaven av The Guardian.
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Denne historien er fra August 29, 2024-utgaven av The Guardian.
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