Red Bull boss Christian Horner has continued his war of words with Toto Wolff, criticising the way his Mercedes counterpart has criticised his own team's recent performances.
Mercedes has scored just six points over the past two races, Monaco and Azerbaijan, its worst performance over two consecutive races since the end of 2012.
After seeing Lewis Hamilton squander a golden opportunity to win in Baku, where the team left without a single point, Wolff said his team needed to perform better in upcoming races.
Speaking after Baku on Sunday, Wolff said: "We just need to be the best, the best of us, and the best that we have.
"And we haven't given the drivers a competitive package this weekend. It's been far from a competitive package.
"That is the frustration. It is not only the incident at the end, that frustrates. It's overall not meeting our own expectations. All of us together: Lewis, the engineers, myself, everybody in the team."
Mercedes is behind Red Bull in both championships but their fight has extended beyond the track in recent weeks.
During the Azerbaijan GP weekend, Wolff and Horner had both spoken publicly about the other during a controversy around Red Bull's "flexi" wing. There were suggestions Mercedes would protest the wing after the race, although that did not materialise.
At one point, Wolff called Horner a "wind bag".
When Wolff's comments from Sunday evening, regarding Mercedes' performance, were put to Horner, he jumped at the chance to continue their war of words.
"I mean, a lot has been made about Toto's comments this weekend," Horner said.
"He's never afraid to roast his team so publicly, which I disagree with. But that's his prerogative."