Max Verstappen and Lewis Hamilton have been called to the stewards' office following their on-track contact in the second part of Sunday's Saudi Arabian Grand Prix.
Hamilton was running behind Verstappen when the Red Bull driver suddenly slowed, allegedly to let his rival through following an order from his pit wall to hand back a position gained earlier on the track.
But a confused Hamilton, surprised by the Dutchman's maneuver, also slowed but rammed the back of the Red Bull.
The Briton initially believed that his rival had brake-tested him, while Verstappen later argued that he had simply slowed to let Hamilton reclaim the first position.
However, the stewards are looking into the incident more closely.
Verstappen and Hamilton have both been summoned for an "alleged breach of Article 2 (d) Chapter IV Appendix L of the FIA International Sporting Code" relating to his maneuver on the main straight.
The stewards' note states the following: "Causing a collision, repetition of serious mistakes or the appearance of a lack of control over the car (such as leaving the track) will be reported to the stewards and may entail the imposition of penalties up to and including the disqualification of any driver."