Rare earth shipments to the US are being cut off by some Chinese suppliers who fear punishment from Beijing, a bad sign for American manufacturers ahead of Xi Jinping's Washington visit.

• A handful of Chinese rare earth companies have stopped shipping to US customers rather than risk trouble at home.
• The trigger was Beijing putting a US supply-chain watchdog group on its countermeasures list in early August, which left suppliers afraid that following Western sourcing audits would be treated as disloyalty.
• Other suppliers halted shipments simply to stay out of the political fight, and some worry the minerals could be resold to buyers under US sanctions.
• Washington says Beijing has not kept its earlier promise to keep export licences flowing smoothly, and the issue is now on the agenda for Xi's September 24 visit.

Outlook: Rare earth supply looks set to stay tight for US buyers unless the two sides strike a deal at the Xi–Trump meeting later this month.