Honda has reportedly reneged on its promise to supply Sauber with customer engines next year.
The claim, carried by Germany's Auto Bild, fuels speculation that the hapless Japanese manufacturer could be about to quit Formula 1 altogether.
The news coincides with speculation that McLaren have looked into dropping their works Honda deal in order to switch to a customer engine supplied by Mercedes, Renault or even Ferrari.
Yet another victim looks set to be the small Swiss team Sauber, with the report saying that the end of the Honda deal leaves them with "no engine" for 2018.
"Honda has dissolved the contract," said the report.
Another reason for the Sauber-Honda split could be that the deal was brokered by Monisha Kaltenborn, who has since been ousted by the Swiss team's new owners.
Since then, rumours of continuing ructions at Sauber have swirled.
Swiss newspaper Blick reported that Beat Zehnder could be named the new team boss, but in fact Sauber announced on Wednesday that the deal with former Renault chief Frederic Vasseur has finally been done.