Jaap de Hoop Scheffer has agreed to a two-year extension of his term as Nato secretary-general into 2009, an alliance official has said.
The official said the Dutch diplomat, who began his term in 2004, would stay on to prepare and preside over a series of high-profile events marking the 60th anniversary of the Western military alliance in 2009.
"He accepted today," the official said. He also said that the exact run-down of the anniversary events - and therefore de Hoop Scheffer's new departure date - had not yet been fixed.
He had been due to leave at the end of this year.
"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.