Hamilton was caught behind his former team-mate at Rascasse, but managed to reverse and creep past the Sauber to return to the pits.
The incident was quickly cleared away and the session resumed after four minutes, with the British champion maintaining his position at the top of the time-sheets.
After complaining that his tyres were dead, the champion spun around and returned to the track in order to get back to the pits.
The incident may have negative consequences for Hamilton's Monaco weekend, ruining his soft tyres, and losing crucial lap time to prepare for qualifying.
Hamilton was not the only driver to make a mistake, with the McLaren of Oscar Piastri also running off the track.
As the session progressed, Hamilton was unable to set a new time and found himself slipping towards the back of the order.
Eventually, the Brit managed to return to the track on a new pair of soft tyres, to make up for lost time and prepare for qualifying.