Mercedes' Andrew Shovlin has hit back at Red Bull's claim that there are "score marks" on the W12's rear wing that appear to indicate evidence of flexibility on the lower elements.
Red Bull team boss Christian Horner has threatened to formally protest against Mercedes this weekend in Qatar, if his team suspect that Mercedes are running the rear wing they've identified as being suspect.
But Shovlin, Mercedes' Head of Trackside Engineering, has said that Mercedes are somewhat perplexed by his claims.
"Well, we've had a look at it and there are no score marks," he told Sky Sports.
"So we're not quite sure what that is, but it seems to be a bit of a story that's not going away.
"From our point of view, we're absolutely happy with what we've got on the car. We've invited the FIA to look at it as much as they want.
"They don't have any issue with what we've got and we go to every circuit, we look at what the fastest wing we have is, and that's the one that we'll bolt to the car - and that's what we'll keep doing.
"We'll work out what's fastest, we'll stick it on the car and will not take advice from another team."
No distraction for Mercedes
Despite the onslaught of back-and-forth off-track sniping between both teams, Shovlin praised Mercedes for keeping their focus under the weight of pressure from Red Bull.
"There are a few sort of mortar shells going across in both directions, probably," he explained.
"But this the team has really come together. What was encouraging to see was, with a weekend like we just had in Brazil, with so much distraction in so many different areas, it was just heads down and get on with the job.
"We've shown the car has the pace to do that. I think Brazil was fantastic for our confidence and for our confidence that we can bring both these championships home.
"It's an amazing place at the moment and everyone's working so hard to deliver that."
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