- Canadian Grand Prix
Red Bull drivers can race in Montreal
"We won't be instructing one driver or the other to concede or overtake," Horner told BBC Sport. "They will be racing each other; the most important thing is they respect they are driving for a team and I believe they do."
Vettel made contact with Webber when trying to take the lead from his team-mate in Istanbul, taking himself out of the race and handing title rivals McLaren a one-two finish.
But Horner said he believed both men had "learnt from what happened" at Istanbul and he had no regrets about allowing the duo to contest the lead.
"We were allowing both drivers to race and I don't think that is wrong. What I do believe is wrong that they unfortunately drove each into each other! Red Bull is about racing, it's not about processions, otherwise we would have given team orders after the first turn or the pit stop.
"We had two guys that we are trying to give equal opportunity to win the world championship and win races being heavily pressured by the McLarens."