Trulli says Toyota must keep pushing

The Cologne-based outfit have enjoyed a strong start to the season and have looked like the fourth fastest team - behind Ferrari, BMW and McLaren - in the first three races of the season.

Trulli reckons Toyota have more potential to extract from their car, something he think swill be necessary if the Japanese squad want to stay in front of their rivals.

"We know that we have some areas where we definitely have to make some progress - which I am not going to tell you," Trulli said in Barcelona.

"But definitely, we have a few areas which we are concentrating on, and where we know that we can get more our of the car. I believe that we have a strong car, basically.

"But now it's time for Toyota to move on, and step up quicker in terms of development work through the season. Nowadays in Formula One, how you start is important, but how you develop along the season is extremely important. This is the key. Toyota has got the resources and the potential, so we have to make it. We have to make it."

The Italian admits all his races so far this year have gone according to plan, but he feels the gap to the top three teams is still too big.

"I strongly believe that at the moment we can be fourth in the championship," he added. "We have got a car that can fight with Red Bull, with Renault, with Williams. It's a lot down to the weekend, and down to the track circumstances. But more or less, I think we can be there.

"So far we have done three races, I made no mistakes and we were always where we should have been. But obviously I can make some mistakes as well, and maybe with one mistake you can slip down two or three positions and you are out of the top 10, and then it becomes a little more difficult.

"If I look back to the Bahrain weekend, that was ... I won't say an easy weekend, but it went exactly as planned without putting in any extra effort. I did exactly what I was supposed to do, and the car did exactly what it was supposed to do. The problem is that the gap between us and the teams in front is still too big.

"During the race I tried to catch Kovalainen, and we were close, close, close, but something was wrong in his car, because as soon as he put on the last set of tyres he was flying - he was the quickest man on the track. That shows that our car is not as quick as their car."