The Force India driver admitted at Hockenheim that within weeks he will have to make a "crucial" decision.
"Anybody would like to drive for Ferrari at some point in their life for what they represent in Formula One," he said.
"With Mercedes, I've been part of that family for a long time. I want to be winning races and championships, that's the important thing, the ultimate goal."
And what about McLaren?
The famous British team also has a theoretical vacancy for 2013, with Lewis Hamilton telling reporters on Thursday he "can't deny" McLaren's form since he won the title in 2008 has been disappointing.
"There are drives everywhere," di Resta told reporters. "It's fairly confusing what is going on at the moment, even with Lewis.
"There's still two (race) weekends to go and I believe that (the August break) is the time when you start to make sure you are putting yourself in the right places and making sure you know what you are doing.
"It is a crucial decision. I'll need to decide pretty quickly what way I want to go."
Di Resta, who recently split with his manager Anthony Hamilton, confirmed at Hockenheim that he is now taking advice from Jenson Button's management team.
"The biggest thing for me is to make sure I'm in a Formula One car next year because that's where I want to be," he said.