In this scenario, are you required to refrain from overtaking the preceding vehicle at the nearest intersection?

Why?

You do not have to refrain from overtaking merely because you are approaching this junction, since sign C-12 identifies a roundabout. Roundabouts are an exception to the ban on overtaking at junctions, but you still need extra care and sufficient space. Overtaking remains prohibited on the pedestrian crossing shown before the roundabout and immediately before that crossing.

art. 24 ust. 7 pkt 3 oraz art. 26 ust. 3 pkt 1 Prawa o ruchu drogowym