Oct.27 (GMM) Lotus' budget has held Lotus back in the second half of 2012, Kimi Raikkonen has admitted.
"We are constantly trying to improve the speed of our car," he said, "but the others have more money and people to develop and that's where the differences are," he said.
"The good news is that despite that we have managed to fight well against the biggest teams. If we are realists, we have done a good job this season," added Raikkonen.
Both the former Ferrari and McLaren driver, and his teammate Romain Grosjean, are expected to be retained by Lotus for 2013.
"The truth is that both drivers have options for next season," team boss Eric Boullier told France's RMC Sport.
"We will make announcements in due time, certainly before the end of the season."
And Boullier grinned: "Look at me -- do I look worried?"