North Korea’s leader Kim Jong Un has announced plans to expand the country's nuclear arsenal at ‘an exponential rate’, according to state media reports.

His announcement comes as China’s president, Xi Jinping, is making his first visit to Pyongyang this week since 2019 – the same year Donald Trump met Kim Jong Un several times for failed talks on denuclearisation.

We speak to the BBC’s Celia Hatton about why China might now be trying to keep North Korea in check.

Producers: Xandra Ellin, Sam Chantarasak and Aron Keller

Executive producer: James Shield

Mix: Travis Evans

Senior news editor: China Collins

Studio manager: Mike Regaard

Digital producer: Tom Bage

Photo: North Korean leader Kim Jong Un speaks during the fifth session of the Ninth Congress of the Workers' Party of Korea (WPK), in Pyongyang, North Korea, February 23, 2026. Credit: KCNA/Reuters

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