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

In the photo you are driving behind a yellow van and approaching a roundabout with signs A-7 and C-12; before the roundabout there is a pedestrian crossing and a cycle crossing D-6b. At the nearest junction - the roundabout - you are not obliged to refrain from overtaking. The answer is: no.

The Road Traffic Act prohibits overtaking a power-driven vehicle at a junction, but excludes from this ban a roundabout and a junction where traffic is controlled. Sign C-12 "roundabout" means that traffic at the junction moves around an island, so it is a roundabout - and you may overtake there, as long as the lanes and the general conditions allow it: adequate visibility, enough space, nobody is overtaking you, and the vehicle being overtaken is not signalling a lane change or an exit. The ban from the Act does not apply, but common sense tells you to judge whether overtaking on the roundabout makes sense - on a small single-lane roundabout there is no room for it. Remember also that before the roundabout, on crossing D-6b and immediately before it, overtaking is prohibited; sign A-7 requires you to give way to vehicles already travelling on the roundabout.

Legal basis: Art. 24 para. 7 point 3 and para. 1 and Art. 26 para. 3 point 1 and Art. 27 para. 4 of the Road Traffic Act (Prawo o ruchu drogowym); § 36 para. 1 of the Regulation on road signs and signals