Engine freeze 2014-2015

[driver x]

I was wondering if the engines can be developed for the 2015 season.
I know they can't change now, the engines are what they are for this season, but can they develop for 2015?
If not, does this mean Renault and Ferrari will always be the weaker engine?

Seems very harsh and by mine opinion unfair. Especially for Renault who is about 70bhp less then Mercedes I believe.
They must have a chance to be back in 2015, right?

 

[Darren Bentley]

over the next few years developments will begin to freeze in certain areas meaning, they can still develop the engine every year but parts of the engine will begin to get frozen