The FIA has been pushing hard all season to clamp down on teams burning oil for performance gains, with a series of technical directives being published.

The latest move came in July, when the FIA informed teams that any new engine introduced from the Italian GP would be allowed a maximum consumption of 0.9 litres of oil per 100km.

However, engines brought in before then would be allowed to use up to 1.2 litres per 100km, handing an advantage to anyone able to get engines ready before Italy.

Mercedes duly introduced its fourth and final power unit of the campaign in Belgium, prompting intrigue about whether or not the timing was related to the Monza oil burn limit.

It is understood that Ferrari in particular was not happy with the situation, because it had been under the impression Mercedes would not introduce a new engine in Belgium, so was caught by surprise.

Suggestions that there had been some form of gentleman's agreement between Mercedes and Ferrari not to introduce an engine in Belgium are understood to have been wide of the mark, however, with sources at both outfits confirming that there had been no discussion between the teams about the matter.

Even so, with the performance gain of the new power unit helping Lewis Hamilton to pole position and victory, the issue of oil burn and any potential extra advantage Mercedes can get will likely mean the topic remains a talking point for now.

Speaking after the Belgian Grand Prix, Mercedes boss Toto Wolff was confident that oil burn would not become a source of conflict between his team and Ferrari – and said he would be more than happy to discuss any issues with his rival.

"We are fierce competitors and the relationship we have is that we stick our heads together if there is a problem, and we discuss it behind closed doors," he said, when asked by Motorsport.com about the oil burn situation.

"It hasn't come up. We need to be careful that things are not made up in the public that are just not right, and not true. So far, I'm easy about it."

Sources have suggested that Mercedes' new engine was worth around one tenth of a second around Spa, so it did play a crucial part in Hamilton's success.

Wolff said, however, that it would be wrong to state it was the essential component that helped it win.

"I think now as it stands you need to extract every single bit of performance, and it was particularly difficult, because we had to balance our qualifying performance versus the race performance," he said.

"And we've given up qualifying performance in the second sector in order to have that advantage in the race. So you have to add all those bits, those milliseconds that add up, to one number.

"That was good enough for us to win today. So everything adds up but I couldn't pick out one element that is responsible."