The latest British soldier to die in Afghanistan has been named as Corporal Simon Hornby, 29, from the 2nd Battalion, the Duke of Lancaster's Regiment.
Cpl Hornby was killed in an explosion while on foot patrol in the Nad-e-Ali area of Helmand on Saturday. The Liverpudlian's wife Holly described him as her "hero".
Cpl Hornby's death brings the total of British service personnel who have died since the start of operations in Afghanistan in 2001 to 240, including 103 deaths this year.
Cpl Hornby had previously served in Iraq, where he was awarded a commendation for discovering an improvised explosive device and for spoiling an insurgent ambush.
He deployed to Afghanistan as a section commander with Arnhem Company, 2nd Battalion The Duke of Lancaster's Regiment as part of the 1st Battalion Grenadier Guards Battle Group, according to the Ministry of Defence.
His wife Holly said: "I am devastated by the loss of Simon. "He was proud to be a soldier and died doing the job he loved. He was my hero."
Lieutenant Colonel Robbie Boyd, Commanding Officer, 2nd Battalion The Duke of Lancaster's Regiment, said he was "courageous" and a "highly respected leader".
"Always happy, always chirpy, he - as did we - lived for his sense of fun, humour and his infectious zest for life; now so sadly taken from him and us," he said.
Cpl Hornby's death came as Defence Secretary Bob Ainsworth declared the international military coalition in Afghanistan would "take the battle to the enemy" in the coming year.
Mr Ainsworth said he could not guarantee the families of Britain's 10,000 troops in Afghanistan that their loved ones would be safe, though he insisted the Government was investing massively to protect them.
And he held out the prospect that 2010 will see some parts of Afghanistan handed over to home-grown security forces, in a process which Prime Minister Gordon Brown has said will eventually pave the way to bringing UK troops back home.
Following US President Barack Obama's announcement of a surge of 30,000 extra troops and the promise of up to 7,000 more from other Nato members - including 500 from the UK - the coalition will be in a position next year to clear Taliban militants from more areas of Afghanistan, said Mr Ainsworth.
The Defence Secretary told Sky News' Sunday Live: "I think General (Stanley) McChrystal's request for 40,000 additional troops will effectively be met by the coalition, so their ability to take the battle to the enemy, to clear the population centres and keep the population safe is now there.
"Yes, there will be operations in the New Year. No, we can't guarantee people that their loved ones are going to be safe.
"But we have invested massively - and will continue to do so - in providing them with all the kit and equipment they need in order to keep them as safe as we can and enable them to do the job that we ask them to do."
Mr Brown earlier praised the "unsurpassed" courage of British troops in a Christmas message, telling them he recognised that this year had "tested your resolve more than any other".
The Prime Minister also spoke of his "gratitude" to the service personnel who have lost their lives, telling the Sunday Mirror: "We owe them a debt we can never fully repay - and we remember too the families they have left behind for whom Christmas will be a heartbreaking time."