Formula 1's governing body imposed a €500,000 ($543,250) fine on the U.S. Grand Prix promoter on Sunday after a post-race track invasion, with €350,000 suspended to the end of 2026.
Stewards said in a statement that the suspended element of the fine depended on there being no further track incursions at the Circuit of the Americas before that date at any FIA championship event.
They recommended that the unsuspended portion "be dedicated to additional motorsport safety by the FIA safety department" and ordered the promoter to submit a formal remediation plan by the end of this year.
Stewards said some 200 people had climbed a small fence and dropped around two metres to the ground between the pit straight grandstand and debris fencing.
They then went under the debris fencing, climbed over a metre-high wall and merged onto the main straight while cars were still on a cool down lap after the chequered flag.
It was noted that the track had never before had such an invasion during the 12 years of hosting Formula 1.