But as he accelerated up the hill, his Red Bull got into a slide and, as he corrected, he ran towards the yellow line that drivers must not cross.
Footage of the incident from Verstappen’s onboard camera was shown during the Monaco GP and appeared to show him running over it, but the view obscured how close his wheels got.
The matter did not appear to have been investigated by the FIA.
Perez had also stopped on lap 22 and, as he exited the pits, he also had a slide that sent him towards the line.
Perez’s incident was noted by the FIA stewards at the time, but no further announcement was made about the matter during the race.
The FIA announced later that both Red Bull drivers have been summoned by the stewards over the incident.
Shortly after the race, Red Bull team principal was in a media briefing when he received a phone call from sporting director Jonathan Wheatley revealing that Ferrari had protested.
It came after Ferrari team principal Mattia Binotto said he believed Verstappen’s actions had been against the rules.
“As Ferrari we are disappointed because we think there was clear breach of regulations on the two Red Bulls for going on the yellow line exiting the pits,” he told Sky.
“I think it was not close. He was on the line and if you look at the sporting code, the wording says crossing.
“Then we had a clarification at Turkey in 2020 to avoid any discussions and, if you look at the race driver notes, it says staying to the right: so staying on the line is breaching the race director notes.
“I think that each single team has the task to follow the race directors’ notes. It is clear and we are still seeking clarification with the FIA.”
Horner said that Red Bull was satisfied that Verstappen had stayed within the line as required by the regulations.
“All the footage we have seen we have been content with,” he said.
Asked if there had been any discussion with the FIA over the matter in the race, Horner said: “Nothing at all.”
Verstappen said that the wild moment exiting the pits was the result of him being super aggressive with his acceleration, which he reckoned was crucial to staying ahead of Leclerc who was right behind him.
“I needed it,” he said about pushing so hard immediately out of the pits.
“Otherwise he would have passed me, because I would not have the traction. My pit exit, that was probably the most fun I had in the race trying to stay ahead.”