Aside from a two-year loan stint with Stuttgart, 32-year-old Lahm has spent his entire professional career with Bayern.
Having worked alongside him for the last three years, Guardiola had nothing but positive words when asked about Lahm's influence.
"I am very happy to have Lahm in my team team. He understands absolutely everything about the game," he told reporters.
"He is one of the best right-backs in history. He is a giant. One of the best memories of my time here in Munich will be that Lahm was my player."
Lahm has made 474 appearances for the Bavarians, from which he has scored 14 goals.