Gordon Brown has signalled the end of the bloody offensive to drive back the Taliban in Afghanistan.
The Prime Minister insisted that Operation Panther's Claw had not been "in vain", despite the deaths of 20 British troops over the past month.
"The efforts of our troops in Helmand have been nothing short of heroic," Mr Brown told the Evening Standard.
"There has been a tragic human cost. But this has not been in vain." Mr Brown said it was now time to "commemorate" the British troops who have died in Afghanistan.
During a constituency visit in Fife, the Prime Minister said it has been "one of the most difficult summers" since troops went into Afghanistan.
He said: "Now that Operation Panther's Claw has shown that it can bring success and the first phase of that operation is over, it's time to commemorate all those soldiers who have given their lives and to thank all our British forces for the determination and professionalism and courage that they've shown.
"What we have actually done is make land secure for about 100,000 people. What we've done is push back the Taliban - and what we've done also is to start to break that chain of terror that links the mountains of Afghanistan and Pakistan to the streets of Britain.
"And I'm very proud of what our forces have achieved over the last few weeks - indeed for all the time they've been in Afghanistan."
The first stage of the operation in the troubled southern province drew to a close as senior ministers urged the stepping up of efforts to engage moderate Taliban elements.