Road priority

So my house and its driveway live next to a main road, although it is through housing and you wouldn't take it as a main road speed bumps have never been put in place for it being a main road, there are several give ways onto the road and there are also cars parked along each side in groups every 20 or so metres. So the question is: Assuming that the right hand lane is blocked at a give way who has priority to joining the main road; Road user 1 who is in the process of turning left onto the main road or road user 2 who is travelling towards the obstructed part of the road meaning he/she has to go into the opposite lane? This is taking into account that both drivers see each other beforehand