Robert Kubica said his Renault team's decision on who will partner him in 2011 is a difficult one to make.

Speculation has surrounded the future of his 2010 team-mate Vitaly Petrov for months although it appears likely that the Russian will be retained for 2011 thanks to his financial benefits.

But the F1 rookie's name was missing from the official entry list published on Tuesday and several big name drivers including Nick Heidfeld, Adrian Sutil and Nico Hulkenberg were also absent.

"This is a difficult subject to get right," Kubica told Dutch magazine formule1.nl. "Of course the team would benefit from a more experienced driver. As a rookie you find that Formula One is not as easy as it first seemed. You also have to say that there have been newcomers who have performed strongly right from the start.

"As for my team-mate next year, the team is in the best position to know what it wants and what position they are in."

Kubica scored over 100 more points for the team than Petrov in 2010 and admitted that with a little more help, Renault could have mounted a stronger challenge for fourth in the constructors' standings.

"All I can say is that we have lost many points this season, for several reasons, but under other circumstances we could have put more of a challenge to Mercedes.

"On the other hand, we need to look at the circumstances we were in at the beginning of the year. You have to respect the reasons for the decisions taken and I think they were the right ones. But how you look at the driver lineup depends on where you are at the time."