Mercedes and Red Bull say they are relying on the FIA to monitor the situation amidst speculation over the legality of Ferrari's ERS.
The speculation surrounds Ferrari's engine recovery system (ERS), which it is claimed is delivering more than the permitted 120kw from the MGU-K.
Though there is no proof, for several weeks it has been claimed that somehow Ferrari has discovered a way of producing an extra 4MJ of energy a lap by bypassing the FIA sensors.
Though the systems were checked in Azerbaijan and Spain it is understood that Ferrari is using new software this weekend which the FIA said to be monitoring, though neither party is willing to comment.
Speaking at today's press conference, Red Bull team boss Christian Horner and Mercedes' Toto Wolff admitted that they are relying on the FIA to keep on top of the situation.
When asked if he was happy with the way in which the FIA is handling the situation, Horner told reporters: "We're not an engine supplier, so maybe Toto can answer more on the engine specifics but there have obviously been some rumours that no doubt you guys are cottoning onto as well.
"I'm sure that the FIA have all the competence to be able to able to measure, administer and look at the car that's presented for scrutineering and during a grand prix weekend," he continued, "and of course it's the team's obligation to ensure that that happens. I think the FIA are probably the best people to point that question at."
"Christian is absolutely right," added Wolff. "We have legality topics come up regularly. Some are more controversial but it's the daily business of the FIA to check what the teams do. It is the obligation of the teams to comply with the regulations and this is an ongoing process.
"I have great confidence with whatever issues are coming up, be it on the engine or the chassis, the FIA has been on top of it a lot. And as far as I understand this is a process that's taking place as we speak and we will see what the outcome is."
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