Prince Harry's regiment is to be sent to Iraq for a six-month tour of duty, defence officials have confirmed.
Prince Harry graduated from Sandhurst last April
Harry would carry out "a normal troop commander's role" serving with his Blues and Royals regiment, they said.
The prince was praised by Prime Minister Tony Blair as a "brave and determined young man" with "a very special character".
He will be the first senior royal to serve on the front line since Prince Andrew in the Falklands in 1982.
This will involve "leading a troop of 12 men in four Scimitar armoured reconnaissance vehicles, each with a crew of three" from the regiment's "A squadron", a joint statement from the Ministry of Defence (MoD) and Clarence House said.
"The decision to deploy him has been a military one, made by Chief of General Staff, Gen Sir Richard Dannatt, in conjunction with Cornet Wales' commanding officer," it added.
"The Royal household has been consulted throughout."
Further details of exactly where Harry, 22, would serve, or his specific role, would not be released because such a move would be "potentially dangerous", the statement added.
Speaking in an interview with the BBC on Thursday night, Mr Blair said Harry's determination to serve in Iraq was "very typical of him".
"He's a brave young man and he's a very determined young man who wants to be part of his regiment and part of the Army," he said.
"I think that shows a very special character on his part."
A Blues and Royals source said Harry, who has long expressed his determination to see front-line action, was "over the moon" at the deployment.
Last year, the prince said: "There's no way I'm going to put myself through Sandhurst and then sit on my arse back home while my boys are out fighting for their country."
In a written statement to MPs, Defence Secretary Des Browne said two squadrons from Harry's Household Cavalry Regiment would be deployed with the rotation of troops to take place in May and June.
The lead formation of British troops, currently 19 Light Brigade, would be replaced by 1 Mechanised Brigade, supported by Prince's Harry's regiment, the statement added.
Prince Harry graduated from Sandhurst in April last year and qualified as an armoured reconnaissance troop leader in October.
His rank of Cornet is used by a small number of cavalry units including the Blues and Royals and is the equivalent of the more usual rank of 2nd Lieutenant.
Known to colleagues as Troop Commander Wales, he is able to lead reconnaissance units known as the Army's "eyes and ears".
Confirmation of the deployment comes after Prime Minister Tony Blair told MPs that 1,600 British troops would return from Iraq within the next few months.
He said the 7,100 serving troops in the south of Iraq around Basra would be cut to 5,500 soon, with hopes that 500 more will leave by late summer.
Prince Andrew, Harry's uncle, was a helicopter pilot in the Falklands conflict.