A soldier was jailed for three years today after pleading guilty to stealing and illegally possessing ammunition which he kept after a training exercise.

A judge told Private Christopher Trussler that he had betrayed the trust of the armed forces and brought disgrace upon his regiment.

Last month Trussler, 29, admitted two charges of illegally possessing and stealing 21 rounds of 9mm ammunition on May 24, contrary to the Firearms Act 1968.

Sentencing him at Chichester Crown Court, Judge Anthony Thorpe told him: "You had no way of knowing what those 21 rounds could have resulted in.

"The offences are aggravated by the fact that you are a serving member of the armed forces."

Father-of-two Trussler, who served with the Princess of Wales's Royal Regiment based at Baker Barracks, Thorney Island, near Chichester, West Sussex, was jailed for three years on each charge, to run concurrently.

Judge Thorpe called for the Army to tighten its procedures relating to the accounting of live ammunition after hearing that Trussler kept the bullets after a training exercise in Northern Ireland.

The judge, who served 31 years in the Royal Navy, said: "Although it is no mitigation, it is clear that the Army procedures over accounting for live ammunition after live firing exercises need to be properly reviewed and I have no doubt that is in hand.

"It is also a matter of concern that you could transport this ammunition from Northern Ireland to England without any form of security screening that should have detected it before you embarked on the transport.

"Again, I hope the Ministry of Defence (MoD) is looking into that as a matter of urgency."

The judge said he would be sending his sentencing remarks to Defence Secretary Des Browne and senior MoD officials.

The court heard that Trussler was caught in an undercover police operation on May 24 when he met a covert officer at a leisure complex in Chichester.

William Emerson, prosecuting, said: "During a discussion, the defendant told the undercover officer that he had 21 rounds of 9mm ammunition for sale, and a price was agreed of £50.

"He also told the undercover officer that he could obtain an AK47 for £1,500. However, it would take some eight weeks for that rifle to be obtained and reactivated. He also said he could get hold of other ammunition."

Following the meeting, the undercover officer accompanied Trussler to a nearby military base and up to 15 minutes later, the soldier returned from Baker Barracks with a box containing live bullets.

Trussler was arrested on June 6 and fully admitted, in interview, selling the live ammunition to the undercover officer, Mr Emerson told the court.

He said: "In interview, he went on to explain his behaviour by saying he was going through a divorce, it was an expensive time for him and he wanted to buy items for his son.

"He explained that he came across the ammunition from a live firing exercise in Northern Ireland and that he had it for a number of months, and admitted to failing to return the ammunition."

The court previously heard that Trussler had convictions dating back to 1996 when he committed two offences of theft.

In 1997 he was convicted of a burglary, in 2000 of an offence of drunk and disorderly behaviour, in 2004 of making a false statement of benefits, in 2006 of obstructing an officer and this year of drink driving.

Judge Thorpe expressed surprise that someone with his criminal record could remain a member of the armed forces.

He added: "Offences involving firearms or ammunition in today's climate of public fear over gun crime and terrorism are always so serious that neither a fine alone nor a community sentence can be justified for them and permit only custodial sentences.

"I have no doubt that the many brave men and women currently risking their lives in the considerable number of armed conflicts in which this country is involved will be horrified at your actions."

Trussler's pre-sentence report showed that Trussler abused alcohol by drinking a bottle of Jack Daniels in the evenings and used Class A drugs on a Friday.