Mbappe is one of football's hottest properties and a host of sides have been linked
with a move for the 18-year-old France international, who scored 26 goals in all competitions as Monaco won Ligue 1 last season.
The French outfit have not named which clubs they believe have approached Mbappe - who has reportedly attracted offers of £100million this summer - but have said they may turn to both the French Football League (LFP) and FIFA to take action against the offenders.
A club statement read: "AS Monaco state with regret that "important" European football clubs have made contacts with Kylian Mbappe (and his entourage) without authorisation from the club.
"AS Monaco want to remind these clubs that such actions are contrary to article 211 of the administrative regulation of the French Football League and to article 18.3 of FIFA's regulation of the status and the transfer of players.
"To put an end to this unacceptable situation, AS Monaco are planning on asking the French Football League and FIFA to start disciplinary procedures against the offending clubs."