A method of and processor for determining a trajectory estimation order for vehicles are disclosed. The processor has access to a section of a road map corresponding to surroundings of the one of the vehicles, and road rules associated therewith. The method includes identifying pairs of vehicles that have intersecting potential trajectories and vehicle priority information indicative of priorities of vehicles on the section of the road map. Based on the vehicle priority information, the method includes determining a trajectory estimation order for vehicles on the section of the road map, such that a given vehicle having priority over another vehicle in the vehicle priority information is above another vehicle in the trajectory estimation order.