"The 26 ambassadors endorsed the extension of his mandate, which will end during 2009, at a weekly meeting of the North Atlantic Council held in his presence," the Nato official said.
Scheffer, 58, has sought to transform the 26-nation alliance that was the Cold War role guarantor of Europe's security into a body able to launch operations worldwide at short notice.
He oversaw the deployment of Nato troops into southern Afghanistan last year in what has become the alliance's toughest conflict so far.