A soldier who gave the order to fire the shots which killed a British tank commander in Iraq broke down as he explained he was trying to protect his friend.

Tank commander Sergeant Scott Manley told the Oxford inquest into Sergeant Steven Roberts' death that he had been trying to stop a rock-wielding Iraqi from attacking him, but his actions tragically backfired.

He said he gave the order to fire on the Iraqi with a lighter weapon, but this jammed.

He said that he did not know the machine gun he then switched to was known to be inaccurate at short range - Sgt Roberts was about 15 metres from his tank when it opened fire.

Sgt Roberts, 33, from Shipley, was killed by shots fired from a Coaxial machine gun mounted on top of Sgt Manley's Challenger tank, one of the three patrolling near the southern Iraqi town of Az Zubayr on March 23, 2003.

Asked what happened Sgt Manley burst into tears and put his head in his hands for several minutes before responding: "Steve turned round and saw the guy quite close to him. He was obviously taken by surprise."

He said Sgt Roberts and the Iraqi circled each other about five metres apart and Sgt Roberts drew his pistol and held out his other hand, indicating his assailant should back down.

When he did not, he said, Sgt Roberts appeared to fire his gun but it seemed to jam and he dropped to his knee to clear it.

He said he took the decision to fire and told Trooper Gary Thornton to use the General Purpose Machine Gun but this jammed. He then ordered that he fire with the Coaxial mounted machine gun, which has a default range of 400 metres and can fire up to a kilometre.

He said: "I was obviously very concerned for my friend and said to Trooper Thornton to lay into the Iraqi guy with his sight.

"The Iraqi guy was hit - his right arm was severed just above the elbow - but at the same time I saw Steve fall to the ground."

He added later: "The only thing I was thinking about was trying to help my friend, that was it - nothing else."

Sgt Roberts' widow, Samantha, left the court during angry exchanges between Sgt Manley and her lawyer, James Rowley QC, over whether the Iraqi assailant posed a sufficient threat to open fire.

Sgt Manley said the man's face was painted or chalked white - a sign of a martyr, he later was told by an Iraqi interpreter.

He said he decided to open fire on seeing Sgt Roberts attempting to fire his Browning pistol, which jammed.

"If he had not drawn his pistol maybe it would have been totally different but he set the stage by drawing his own weapon and firing or attempting to fire," he said.

Oxfordshire Assistant Deputy Coroner Andrew Walker asked him: "Did you feel you had any choice but to use the Coaxial?"

He replied: "I didn't really have time. It was just a decision that was made at the time."

Sgt Roberts died three days after being ordered to hand back his body armour due to shortages and Brigadier David Martin, who was a colonel responsible for channelling equipment to soldiers in Kuwait and Iraq at the time, gave evidence at the hearing.

Mr Walker asked him how Sgt Roberts found himself in a war zone without the protective clothing that would have saved his life.

He responded: "I am not sure I can give you a full and comprehensive answer."

The coroner pressed: "But you are responsible for supplying what makes it over to Kuwait and to the troops. What was required was not making its way over there. What, from your point of view, went wrong?"

Brig Martin explained that in autumn 2002 it was decided that all troops in combat would be equipped with Enhanced Combat Body Armour.

The aim was to top up the stockpile of body armour to 37,000 sets - there were 46,000 people in the theatre of operation - and the order was placed for it to be received by March 2003.

However, he said, the last consignment was not delivered until April 4, after the war had begun.

The coroner asked: "So it was known at the time that there would not be enough body armour to go around?"

Brig Martin replied: "It is a matter of public record that a number of operational requirements were not received by the time hostilities commenced in March 2003."

He said that whereas large stocks of equipment were kept during the Cold War and the First World War, in today's "wars of Choice", he said, "equipping for each and every likely option is un affordable and unrealistic.

But he added that the department had learned lessons from the Iraq war and now had stockpiles of items.