US President Barack Obama has set out an ambitious timetable for the deployment of an additional 30,000 soldiers in Afghanistan and the start date for military withdrawal.
In a highly anticipated address, the US leader said the troop surge would take place at the fastest pace possible, swelling the total American presence in the region to almost 100,000 by next summer.
But the commitment will not be open-ended. It is envisaged that an Afghan security force will be trained to a sufficient level to enable the US to start pulling troops out as early as July 2011, Mr Obama said.
The new strategy consists of three core elements: a renewed military effort; a civilian surge to reinforce positive action; and an effective partnership with Pakistan, Mr Obama said.
Speaking at a military academy in West Point, New York state, Mr Obama acknowledged the difficulty allied forces face in reversing the fortunes in the flagging conflict.
Afghanistan is not lost, but for several years it has moved backwards, he said, adding that the Taliban had gained momentum, while the Afghanistan-Pakistan border remained a safe haven for al Qaida. These are the resources that we need to seize the initiative, while building the Afghan capacity that can allow for a responsible transition of our forces out.
This withdrawal will commence within 18 months, he pledged. Mr Obama added that the US's military aim in the region remained the same: To disrupt, dismantle and defeat al Qaida.
He said: The 30,000 additional troops that I am announcing tonight will deploy in the first part of 2010 - the fastest pace possible - so they can target the insurgency and secure key population centres.
He also pushed other members of the coalition to up their presence in a bid to end the conflict, saying: Some have already provided additional troops, and we are confident that there will be further contributions in the days and weeks ahead. Our friends have fought and bled and died alongside us in Afghanistan. Now, we must come together to end this war successfully.
For what's at stake is not simply a test of Nato's credibility - what's at stake is the security of our allies, and the common security of the world.