Mercedes boss Toto Wolff has insisted that the team will oppose proposals to implement rules allowing engine development during the season.
Currently, rules state that engine changes cannot be made after the season has begun in order to keep costs down.
However, ahead of a Formula 1 commission meeting regarding the matter, Red Bull and Ferrari are keen to see the rules relaxed in order to boost their chances of competing.
"I don't think we will change our mind in the next month, whenever the commission meeting is going to take place," Reuters quotes Wolff as saying.
"We were asked to guarantee supply of engines at the same specification, at the same time for all the customers at the same price. And we can't supply them at the same time if we are having in-season development."
Mercedes, who have won 13 of 16 races so far in the 2014 campaign, clinched the constructors' championship last Sunday in Russia.
