A large force of extra troops is expected to be sent to Afghanistan in response to the escalating violence facing British forces in the country.
Meanwhile the father of the latest British soldier to be killed, Pte Damien Jackson, 19, said that he and his family could not "support or condone" the policy of the Government, which put "our young men and women in such dreadful danger".
Pte Jackson, from South Shields, Tyne and Wear, was in the 3rd Battalion, the Parachute Regiment. He died in an ambush in the town of Sangin, Helmand province, on his way to clear a helicopter landing site on Wednesday.
At the time of the initial deployment in Afghanistan, the then defence secretary, John Reid, declared the three-year-long mission may end without a shot being fired.
Hamid Karzai, President of Afghanistan, said the violence besetting his country could not be solved by military means alone. The Taliban attacks would continue while the fighters could take refuge across the border in Pakistan.
Des Browne, Secretary of State for Defence, said he had received an official request for reinforcements from military commanders and was considering it "as a matter of urgency". But the claim, that the new heavily-armed force would replace about 800 engineers and logisticians was last night dismissed by the Ministry of Defence as "speculation".
More British forces are expected to arrive in Afghanistan in several stages. An initial "flexible" infantry force of several hundred troops is likely to be sent as soon as possible to the Sangin valley, which has become a constant battleground between the Taliban and British and Nato forces.
Mr Browne revealed there were already more than 5,000 British troops in Afghanistan, compared with 7,200 in Iraq. Defence sources said the size of the Afghan force, already more than that sent during the 2001 war, may outstrip the Iraq deployment by the end of the year.
Yesterday's announcement came after the deaths of six members of the British forces five of them in the past nine days and Tony Blair's acknowledgement that the troops face a long and hard fight against a resurgent Taliban.
Pte Jackson joined the Army in November 2003 and completed his basic training at the Infantry Training Centre at Catterick, North Yorkshire, before joining the Parachute Regiment's A Company in June 2004. He had served in Northern Ireland and Basra, southern Iraq, before being posted to Afghanistan.A keen football fan and Sunderland FC season ticket holder, he also enjoyed athletics and ran for his local athletics club, the South Shields Mariners.
His father, Daniel, said: "I wish everyone to know just how extremely proud I am of my son Damien of all that he has achieved in his lifetime and of the fact that he died, when duty called, protecting others, in the service of his country. A fine, upstanding South Shields lad, Damien was immensely proud to have achieved his ultimate ambition in becoming a member of the finest regiment in the British Army.
"My family and I are desolated but we will strive to seek inspiration from the example of his courage."
He added: "We fully support the British Army in Afghanistan while in no way supporting or condoning a government policy that has placed our young men and women in such dreadful danger."
Pte Jackson's commanding officer, Lt-Col Stuart Tootal, said: "Private Damien Jackson was an excellent young soldier who represented the very best of what being a paratrooper is all about.
"Damien died doing the job he loved and fighting to protect his fellow paratroopers. One of the very best in all respects, he will be sadly missed by all his comrades and our thoughts are with his family and friends at this difficult time."
Mr Browne said he was "greatly saddened" by the death. He said: "He, like all our troops in Afghanistan, was bringing security and stability to Helmand so that the Afghan people can rebuild their country."