Lando Norris was unimpressed with Max Verstappen's defending after picking up a penalty for leaving the track and gaining an advantage at the United States Grand Prix.

The two title contenders enjoyed a mighty battle during the closing stages of the race, but tempers flared when Norris attempted a move around the outside at Turn 12.

To defend, Verstappen lunged deep and didn't make the corner, forcing Norris wide. The Brit didn't yield though and attacked around the outside, taking the position when the outside became the inside at Turn 13.

Verstappen jumped onto the radio immediately, calling for an investigation into Norris for overtaking off the circuit. The McLaren driver, meanwhile, complained that his rival forced him off the track.

The stewards noted the incident and after a brief review, Norris was slapped with a five-second time penalty. When the chequered flag dropped, this relegated him back behind Verstappen, costing him a podium finish.

Discussing the incident post-race with Sky Sports F1, Norris said: "It's impossible to know. They obviously can't make their minds up for a few laps. It's obviously not an easy decision otherwise it would have come a bit sooner.

"I tried. He also went off the track, so if he goes off the track clearly he's gone in way too hard and also gained an advantage by doing what he did."

Addressing the battle with Verstappen at the start, Norris continued: "From inside the car it's obviously harder to say on some things and also easier to say with some things. He'd obviously committed quite a bit, which he has the right to do. But again, he went completely off the track...

"I don't know, I need to look back at it. [It is] the same point. He's overtaken by going off the track... what do I do? He defends by going off track, he attacks by going off track. But I'm not going to complain about it. I think Max drove well, he defended well and we had a good race together. But the rules are the rules."