Lewis Hamilton has admitted he is unsure about the reasons behind improved pace for his Mercedes car in recent weeks, responding to comments made by Red Bull chief Christian Horner.
Red Bull are continuing to question the power-gains of their Formula One rivals throughout the season, believing that ongoing work has been done to their title rivals' car.
Following the Turkish Grand Prix, Horner directly addressed those views by saying: “Their straight line speed has taken a significant step recently. Whereas we could match them with smaller wings previously, now we can’t get near.
"Lewis in particular had a significant straight-line advantage with a bigger rear wing on the car. We’ve got to maximise our package as best we can and as I say it’s surprising that they appeared to have made the step that they have with the power unit.”
However, those claims have been rebuffed by defending champion Hamilton as he's admitted he doesn't know why there has been speed improvements.
“We haven’t done anything to the car so I don’t really know why that is the case," he said, adding that he believes the two previous tracks suited Mercedes better.
“I think the two tracks that we’ve just driven on have maybe suited us a little bit more."
Hamilton finished fifth in Istanbul, having taken a penalty for a power unit change, and issued praise to teammate Valtteri Bottas - who is leaving the team at the end of the season.
“The car has been feeling good. It felt great this weekend and moving forwards, Valtteri did a great job.
"If he can continue to perform like that over the next races, it will be good for the team and if the car continues to behave as it has this weekend, that is good for us."