Are you allowed to start overtaking a vehicle at this section of the road?

On the visible section of the road, there is a horizontal marking P-4 'Double solid white line', which separates lanes of opposite directions. According to § 86 para. 4 of the Regulation on road signs and signals, this sign indicates a prohibition on crossing this line or driving over it. Since overtaking the vehicle in front of you would require crossing this line, the manoeuvre is prohibited in this situation.