When overtaking on an urban road, it is important to maintain an **adequate lateral separation** from the vehicle you are overtaking. This separation is not fixed but should be **proportional to the speed and the characteristics of the road**.

- **Speed**: At higher speeds, more space is needed to react to any unforeseen events. Therefore, if you are driving fast, you should increase the lateral distance to ensure safety.

- **Road conditions**: If the road is in poor condition, such as with potholes or slippery surfaces, it is crucial to leave more space. This also applies if there are adverse weather conditions like rain, snow, or fog, which can affect visibility and vehicle control.

- **Traffic and environment**: If there are many vehicles on the road or if the traffic is dense, it is advisable to increase the separation to avoid collisions.

In summary, the lateral separation when overtaking should be adjusted according to the **speed** and **road conditions**, thus ensuring a safe and efficient maneuver.