Sergio Perez has said that he will wait until after Friday's practice sessions before deciding whether to continue with the remainder of the European Grand prix weekend.

Two weeks ago the Mexican admitted to feeling unwell following the opening practice session, the youngster still feeling the after effects of his horrendous crash at Monaco.

Speaking to reporters at Valencia today, the 21-year-old said that the Swiss team would allow him to make the decision as to whether to contest the entire weekend, admitting that there was no pressure on him to do so.

"It is all up to me, as it was in Montreal," he said. "They told me if I was not feeling right to come and speak to them," he added, referring to the doctors who had cleared him to participate in Canada following his Monaco crash.

"We will not have any checks, they all trust me and if I feel fine I will drive here. If I still feel dizzy, I will not drive. But I have prepared very well to be ready for the weekend.

"The doctors always thought that we were a bit too optimistic to go back after the accident because it was a very big accident, the one that we had in Monaco," he continued. "I never had one like this before but I think you need quite a bit of time to recover. I was feeling alright in Montreal, I was feeling a bit dizzy but I was quite optimistic... but after the first session, even though the time was quite competitive, I was not feeling 100 percent, I was not feeling good at all. I was feeling very dizzy on the change of direction so I decide together with the team to wait a bit more and go back when I was 100 percent right."

McLaren test driver Pedro de la Rosa, who deputised for Perez in Canada, remains on call this weekend, Sauber choosing the services of the Spanish veteran over its own reserve driver 19-year-old Esteban Gutierrez.

"Of course as a driver you always want to drive," said Perez, "but I think he's just not ready. I think the team has done a good decision because they will bring him step by step. Peter Sauber knows very well how to do this. Peter has taken the right decision."