The FIA has clamped down on track limits abuse at Mexico City's Turn 11, telling Formula 1 teams that qualifying times will be deleted if drivers run wide.
Following the drivers' briefing on Friday afternoon, F1 race director Charlie Whiting outlined the new policy in revised race notes sent to all the teams on Saturday morning.
Ahead of qualifying, he explained that drivers running too wide at the exit of the left-hand Turn 11 will lose their times.
Whiting said: "If a driver crosses the kerb on the exit of Turn 11 during qualifying and, as a result, no part of the car remains in contact with the red and white section of the kerb, the lap time of the driver concerned will be deleted by the stewards.
He also confirmed that abuse of track limits at Turn 11 would be penalised in Sunday's race.
"During the race a black and white flag will be shown to any driver who clears the red and white section of the kerb three times," he noted.
"Any further occurrence will then be reported to the stewards. Each time any car clears the red and white section teams will be informed via the official messaging system."