Red Bull will not use a new 'MGU-K' unit supplied by Renault this weekend in Austria.
Marca reports that Renault has been using the 2017 version of the energy recovery component so far this year, but that the new specification is finally ready.
Power unit could be used in Austria
However, fitting the new unit will result in penalties for the Renault-powered drivers, including those at the works team, McLaren, and Red Bull.
"It will be available in Austria for all the cars that want it.
It so happens that not all the teams have chosen to use the new specification, but it's something that we've been very much waiting for," said Renault boss Cyril Abiteboul.
It is believed Renault and McLaren will use the new MGU-K in Austria, but Red Bull doesn't want to take penalties at its home race at the Red Bull Ring.
"It's a problem that some have chosen not to use it. It means they will continue to use the MGU-K of a previous technical specification with a higher reliability risk.
But that is our philosophy - to accept the choice of the teams that have all the information," Abiteboul added.