Kamui Kobayashi has criticised his Caterham team for not making enough improvements to the performance of their car, which has seen the constructor rooted in last place.
The Leafield-based team have seen fellow long-time backmarkers Marussia pick up their first points in Monaco, but 27-year-old former Sauber driver Kobayashi believes that his colleagues need to do more if they want to avoid finishing last in the constructors' rankings.
He told Crash.net: "I definitely push myself really hard and also the team as well because we need the motivation and the team is not in an easy situation. So I think we need to keep up our maximum performance always.
"We never know what's going to happen in the future but at least the new owners promised updates which is very positive. It means we can look for the performance, we can look in to the data.
"The last couple of months we have struggled not having updates so it was a very difficult time. But now we have good signs to get some new parts."
Kobayashi made his Formula 1 debut with Toyota in 2009.
