Red Bull has confirmed the team will use the flexing rear wing that Mercedes is threatening to protest at this weekend's Azerbaijan Grand Prix.

This latest flashpoint between the top two teams began back in Spain, when Lewis Hamilton highlighted Red Bull's 'bendy' wing after qualifying and noted the potential advantage it could give them on Baku's long straights.

In the days after the race, the FIA confirmed new load tests would be introduced but only from the French GP, much to the anger of Mercedes boss Toto Wolff, who called the delay "incomprehensible".

The Austrian then confirmed not only would his team protest Red Bull if they used the wings in Baku but potentially take legal action to the International Court of Appeal if the initial protest failed.

However, responding to Wolff, Red Bull advisor Helmut Marko said his fellow countryman's comments were likely just bluster.

"Mercedes would have to protest against eight cars," he told F1-Insider.com.

"Because in addition to us, Ferrari, Alfa Romeo and Alpine are also impacted. Do you really want to do that and cause a major scandal? I do not think so.

"We expect that the tests for the front wing will now also be tightened, that's just fair. Because especially the front wing of Mercedes is the most wobbly candidate in this area. In any case, there is also potential for protest."

Indeed, a common rebuttal for Red Bull has been to warn of their own protest against Mercedes over their front wing, which does appear to bend more than the one on the RB16B.

“It is part of Formula 1 that the teams look closely when the competition has something special on the car,” Marko added.

“That’s what we did when Mercedes came up with DAS last year. The FIA declared the system illegal, but they were still allowed to use it until the last race.

“We accepted that. Why don’t Mercedes now accept the same thing with our rear wing?”

This matter of flexi-wings isn't limited to just the top two teams, with McLaren joining Mercedes in voicing anger at the wait for new load tests, while Alfa Romeo touted cost concerns over having to design a new rear wing that meets the FIA's new requirements, with a figure of $500,000 mentioned by Red Bull.

As for whether the potential protests this weekend in Baku have any chance of succeeding, F1 motorsport boss Ross Brawn is doubtful.

“No, I don’t think so," he said after Monaco. “I think the FIA have been pretty consistent with their approach. I’d be amazed if the stewards go against the opinion of the FIA.”