Prince Harry and his squadron from The Blues and Royals have received their marching orders to deploy to Iraq in May despite yesterday’s announcement that 1,600 British troops will be withdrawn at that time.

Second Lieutenant (or Cornet) Wales will be leaving with A Squadron The Blues and Royals, Household Cavalry, as part of the next rotation of troops for Operation Telic.

As Tony Blair made his long-awaited statement that British forces can start thinking of returning home, the Prime Minister refused to apologize for the Iraq war. Facing calls from MPs to take responsibility for the chaos that came after the invasion, Blair declared that terrorism would be defeated "when we do not apologize for our values but stand up for them."

No details have been given about the Prince’s responsibilities, but he is likely to serve with his squadron wherever it is deployed. This could mean being posted to Maysan province for reconnaissance along the border with Iran. Prince Harry has already made his wishes clear. He wants to be with his squadron, not locked away in a staff job in a heavily protected base.

Every attempt will be made to treat Cornet Wales like any other junior officer, but his commanding officer will have a special responsibility to secure his safety. That will not mean surrounding him with bodyguards while on patrol, but he is expected to have a personal protection officer when required.

The deployment of A Squadron The Blues and Royals is expected to be announced today. The present formation in southern Iraq, based around the 19th Light Brigade, will be replaced by the 1st Mechanized Brigade, and the total British presence will be cut from just over 7,100 to about 5,500.

The cutback of 1,600 is much smaller than had been predicted. The military had planned for a cut of more than 3,000 by the spring. Blair said that it would be possible to reduce the presence to fewer than 5,000 by the end of the summer if the conditions were right.

Diplomatic sources in Washington told The Times that the White House had been unhappy with Blair’s announcement so soon after Congress had delivered its rebuke of the planned increase in U.S. troop levels in Iraq. Although President Bush had long been aware that Britain was likely to begin withdrawing troops this year, he believed that “the timing of this was not helpful,” with aides asking if this “really needed to be done now."

Howard Dean, a leading Democrat, described the British pullout as “a clear setback for the [Bush] Administration that is just simply out of step with our allies.”

The regiments bound for Iraq in May will include the Irish Guards, the 2nd Battalion The Royal Welsh Regiment and the 2nd Battalion The Royal Green Jackets, now the 4th Battalion The Rifles.

The cutback was relatively small-scale because of the judgment that the threat from militant extremists in southern Iraq remained high. Underlining the dangers facing British troops in overseas operations, the Ministry of Defense said yesterday that a Royal Marine from 45 Commando had been killed by a mine in Sangin, northern Helmand. He is the 47th British serviceman to die in Afghanistan since 2001.

Blair encountered an outspoken intervention from Sir Malcolm Rifkind, the former Tory Foreign Secretary, who said that Blair should apologize for the “virtual disintegration” of Iraq.

Sir Menzies Campbell, the Liberal Democrat leader, appealed to Blair: “Will you ignore the voices in Washington arguing and perhaps even preparing for military action against Iran? Nothing you say today will persuade those who voted against military action against Iraq.”

Blair told MPs that British troops would remain in Iraq to support local authorities into 2008 “for as long as we are wanted and have a job to do”.

The pullout had been made possible by Operation Sinbad, in which British and Iraqi forces removed insurgent hotspots and supported reconstruction in Basra, he said. “What all this means is not that Basra is how we want it to be, but it does mean that the next chapter in Basra’s history can be written by Iraqis.”