Dutch chipmaker Nexperia has suspended wafer deliveries to its Chinese assembly plant, a letter to customers showed, potentially intensifying a supply crunch that is worrying automakers globally, Reuters reported on Friday.

The letter, dated October 29 and signed by Nexperia’s interim CEO Stefan Tilger, stated that the suspension, effective October 26, was “a direct consequence of the local management’s recent failure to comply with the agreed contractual payment terms.”