In a statement, Leeds wrote: “Leeds United can confirm that we have received Garry Monk’s resignation from his role as First Team Manager.
“We are shocked and disappointed by Garry’s decision but his resignation has been reluctantly accepted by Chairman Andrea Radrizzani.
“Andrea made it clear to the media yesterday that his intention was to exercise the Club’s option to extend the Manager’s contract for another 12 months and immediately begin negotiations for a longer term deal.
“Mr Radrizzani has met with Garry twice since taking over at Elland Road earlier this week and during the second meeting yesterday it became clear that Garry was considering life beyond Leeds United as at no time did Garry wish to discuss terms for a longer contract.
“Following that meeting yesterday Garry’s agent requested that the option was not exercised and his resignation was received this morning.”
Garry Monk was appointed as head coach of Leeds United last summer and guided them to seventh in the table.
The 38-year-old was expected to sign a new deal following Massimo Cellino’s exit, but the former Swansea City boss has decided against a second season in West Yorkshire just two days after Andrea Radrizzani completed his takeover of the club.