Leclerc unleashed an X-rated tirade over team radio, where amongst a hoard of expletives, he appeared unhappy that Sainz had overtaken him during the race.
The Monegasque driver returned to the track after his second pitstop ahead of his team-mate but was immediately overtaken by Sainz, with this move appearing as the cause of Leclerc’s anger.
Following the race, Sainz refused to elaborate on the incident, and claimed he would not fight his cause in front of the media, but failed to hide there was a split between the driver duo.
According to Quotidiano Sportivo, Ferrari team boss Fred Vasseur summoned the two drivers to a meeting after their fallout, and chastised them both for their behaviour at the Las Vegas GP.
"Frederic Vasseur immediately summoned Leclerc and Sainz after the race, and sent a clear message to both drivers: "Nobody is asking you to be best friends, you still have two weekends to spend together and Ferrari expects, even demands, loyal collaboration,” the report read.
"Because the constructors' world championship is at stake and giving up the remaining hopes in the name of individual whims would be intolerable."