However, following negotiations with the 26-year-old, Pompey have pulled out of the deal and will now focus elsewhere to strengthen their striking options.
It is understood Ladapo’s wage demands were chiefly behind the breakdown of the potential transfer.
Pompey are closing in on the free transfer signing of Gary Mackay-Steven from Aberdeen, while James Bolton has arrived from Shrewsbury.
But Ladapo will not be joining the pair at Fratton Park in the forthcoming season as Kenny Jackett turns his attention to other attacking targets.
Plymouth, who were relegated to League Two last season, must now seek another buyer for the ex-Crystal Palace forward.