German semiconductor giant Infineon has said its proposed acquisition of US computer chip specialist Wolfspeed has run into opposition from US regulators over security concerns.
The German firm had announced last year that it planned to buy Wolfspeed from US group Cree for $850 million (800 million euros) to boost its position in radio frequency and power solutions, but it said the deal now looks unlikely to go ahead.
"The Committee on Foreign Investment in the United States (CFIUS) informed Infineon and Cree that the transaction poses a risk to the national security of the United States," the German company said in a statement late Wednesday.
Since the US body did not propose any remedies that might alleviate those concerns, "there is a considerable risk that the transaction, as agreed, is not going to close".
Cree, in a statement of its own, said both sides were exploring ways to address the US concerns, but warned that there was "no assurance" that even a revised deal would be approved.
No details were given about the nature of the security fears, but it comes as US authorities have shown a growing willingness to halt deals they believe could pose a national security risk.
Last December, the planned purchase of German semiconductor equipment maker Aixtron by a Chinese company fell through because of CFIUS objections, amid fears that Aixtron technology could have military applications.
Explore further: US moves to block Chinese purchase of German tech firm Aixtron (Update)