(CNN) -- A former Norwegian prime minister has been appointed to lead NATO, the alliance said Friday.
Jens Stoltenberg, 55, has been named to the secretary-general post held by Anders Fogh Rasmussen and will begin his new job on October 1.
Stoltenberg is "the right man to build on NATO's record of strength & success," Rasmussen said via Twitter.
Stoltenberg served as Norway's prime minister two times, first ascending to the position in 2000 at age 40. His last term ended October 2013.
During his tenure as prime minister, Stoltenberg often called for NATO to focus on security challenges close to Allied territory, according to NATO's website.
He is now the U.N.'s special envoy on climate change and serves as the Norwegian Labour Party's parliamentary leader.
Rasmussen, a former prime minister of Denmark, has been NATO secretary general since 2009.