You must give way:

  

An obligation to give way requires you to give clear indication of your intention to give way to other vehicles by slowing down or stopping in plenty of time.

You must give way:

At uncontrolled pedestrian crossings where pedestrians have already stepped out or are just about to step on to the crossing.

As you turn onto the road from a parking lot, a gas station, a residential area, a pedestrian way, the hard shoulder or an off-road area.

This is known as the Exit or Entering Rule.

To traffic coming up from the left. Vehicles approaching a junction or crossroads from the left have priority.

This is known as the Left Hand Rule.

To oncoming traffic as you prepare to turn left and to all vehicles using the carriageway you will enter as you make the turn.

This is known as the Turning rule.

As instructed by traffic lights and traffic signs

Note: You must not attempt to pass through the crossing if by so doing you might obstruct, impede or endanger other road users.