Kimi Raikkonen believes he will have to be wary of Sergio Perez in future after suggesting he can no longer trust the Mexican on track.
Ahead of this weekend's Canadian Grand Prix, the fallout from Monaco – where Raikkonen and Perez collided – continues to be felt.
A heated Raikkonen, who endured another brush with Perez in Bahrain, suggested that "maybe someone should punch him in the face" to teach him a lesson given the number of incidents he has been involved in this season.
Perez is adamant he did nothing wrong in Monaco and sees no reason why he should clear the air with Raikkonen ahead of Sunday's race around Montreal's Circuit Gilles Villeneuve.
Asked whether he may have to be cautious when close to Perez in forthcoming races, Raikkonen said: "Sometimes you have to with some guys, because you cannot trust them.
"If you take maybe the top five guys, you trust them because you know if they are there they are not going to turn into you, that they are going to race fair.
"We can be hard, but we can be fair. It's okay to be aggressive, but you have to have some idea behind what you're doing when you overtake and not just hope the guy ahead of you is going to move over.
"You know certain guys will race hard and fair, but with some guys you do not know what to expect."
Raikkonen does not think Perez will change his ways despite speaking to FIA race director Charlie Whiting post-Monaco. "I spoke with the stewards and they thought it was a racing incident, but I don't really see it like that," Raikkonen added.
"They said I did nothing wrong, but there has to be somebody who did something wrong. Nothing is going to change. I know Charlie has spoken to Perez, and I don't know what he spoke about. But there was nothing I could have done apart from drive straight. I was using my line and I could easily have made the corner.
"But if he comes in too fast and can't stop – while I was in the middle of the circuit – there was no way he was going to get past me unless I moved over.
"I don't really feel I should move over if another guy is too fast."
Running fifth at the time, Raikkonen was forced to pit after his collision with Perez after sustaining a puncture, relegating him to 16th.
Although producing a stunning recovery in the closing laps to claim 10th, Raikkonen goes into Sunday's race 21 points behind championship leader Sebastian Vettel.