NATO named the British ambassador to Iran, Simon Gass, as the alliance's new top civilian envoy in Afghanistan on Wednesday, to help steer the handover of the security role to Afghan forces.
Gass will replace another Briton, Mark Sedwill, who has served as NATO's senior civilian representative since February 2010, the 28 nation military organisation said in a statement.
He will officially take over at a meeting of NATO foreign ministers in April.
Gass will take up his duties during a crucial year that will see the NATO led mission begin to hand over security responsibility to Afghan forces, with the goal of giving them control of the battlefield nationwide by 2014.
"Ambassador Gass is a highly qualified diplomat who will bring a regional perspective to this important post," NATO Secretary General Anders Fogh Rasmussen said in a statement. "He knows how important the civilian and political aspects of NATO's engagement in Afghanistan are, especially as Afghans start taking the lead for their own security in the first half of this year," he said.
"At the same time, I want to thank Ambassador Mark Sedwill for his sterling work in strengthening the political component of our engagement in Afghanistan," Rasmussen said.
Gass will be the face of NATO's political leadership in Kabul and his job will be to coordinate the governance and development work with the military campaign.
"We are entering a period of transition in Afghanistan which will be critical for the country's stability and security," Gass said in the NATO statement.
NATO hopes to build up Afghan security forces to 306,000 soldiers and police by the end of the year to begin taking over from around 140,000 foreign troops fighting across the nation.
The United States, the biggest contributor to the war effort, plans to begin drawing down troops in July, if conditions on the ground permit it. At the same time, the alliance stresses that good governance was vital to ensuring a smooth transition to an Afghan lead.