Mercedes boss Toto Wolff described Lewis Hamilton's crash with Max Verstappen at the Italian Grand Prix as a "tactical foul" by the Red Bull driver.

The drivers' championship front-runners collided at Monza, having also come together at the British Grand Prix, forcing both to retire from the race.

After labouring behind eventual winner Daniel Ricciardo, who led a McLaren one-two, Verstappen's hopes of victory were seemingly dashed with a pit stop that saw him stationary for 11.1 seconds.

Hamilton then emerged from his pit stop at the start of lap 26 alongside Verstappen, who attempted to sneak down the inside at turn two, only to catch the kerbs and send his car airborne before it landed on top of the Mercedes, with both ending up in the gravel trap.

Having come second in the sprint race, Verstappen extended his championship lead by two points. He now holds a five-point advantage.

The incident is the subject of a stewards' investigation, but Wolff indicated he believes the blame lies with the Dutchman.

"The stewards are going to decide who is to blame. There is predominantly to blame, I guess, we've seen that in the past. I think in football you'd say it was a tactical foul," Wolff told Sky Sports. 

"He probably knew that if Lewis stays ahead, that is the race win possibly.

"I think when you look at turn four, Lewis backed out and that was quite a thing because probably you know he's staying ahead of you. And then incidents where they actually crash, it was clear for Max in there that they would crash.

"I think if we don't manage that in the right way, this is going to continue. They had a high-speed crash at Silverstone, we had one car ending on top of the other one on Lewis' head here, so how far can you go? Maybe next time we'll have a high-speed crash and land on each other."

Hamilton added: "I was racing as hard as I could, finally got past Lando [Norris], I was in the lead so they pitted me, pit-stop was obviously slow, lost a couple of seconds.

"I came out, saw that Daniel came past, Max was coming, I made sure I let a car's width on the outside to him. I went into Turn 1 and I was ahead, I was ahead going into turn two, then all of a sudden he was on top of me."

Asked if Verstappen could have backed out of the corner, Hamilton replied: "Absolutely. Exactly the same scenario that happened in turn four, where I went around the outside, I was in exactly the same position, but I gave way. And that's racing.

"He just didn't want to give way today, he knew when he was going into turn two what was going to happen, he knew he was going over the kerb but still did it. We'll speak to the stewards and we'll see."