The teenager charged with the murder of Watford youth Koy Bentley went into the witness box on April 12 at St Albans Crown Court to begin his evidence.
The 16-year-old is accused of stabbing 15-year-old Koy to death at a flat in Watford, which they were using along with a third man to sell crack cocaine and heroin from.
The defendant, who was 15 at the time of Koy’s death last June, is alleged to have stabbed him twice in the chest, with one wound proving fatal.
The teenager, who can’t be identified for legal reasons, began his evidence and was asked by his barrister David Etherington QC: “Did you kill Koy Bentley?”
The boy replied: “No Sir.”
Mr Etherington then asked him: “Did you want to hurt Koy at all on the day he died?”
He replied: “No.”
The barrister then asked “Did you ever want to hurt Koy?”
He replied: “No Sir.”
The teenager has pleaded not guilty to murdering Koy on the afternoon of June 5 last year at a flat at Rainbow House in Water Lane, Watford.
The prosecution alleges that Koy, who lived in Watford, the accused and a 21-year-old man who can’t be named, were involved in selling Class A drugs from the flat.
During the trial the jury have been told that at the time of the murder two women who had just bought drugs from the three were in a bedroom taking them.
The fatal knife wound passed through Koy’s ribs, into the chest cavity, through the lower left lung and into his heart, a jury was told.
The jury have been told that it was a sudden disagreement between the accused and Koy in the lounge area of the flat that afternoon that sparked the violence.
After the killing, the accused and the 21-year-old man are said to have run from the flat.
The defendant, said the older man as he gave evidence to the court earlier this month, hid the knife under a bush in an alleyway.
The court has heard how detectives later recovered the kitchen knife.
In the witness box the accused told the jury he had been brought up by his mum in North West London before they moved with his sister to the Westminster area living in an estate know for gangs.
The teenager said he had got involved with drugs and started taking cannabis at the age of 13.
He said when he was 12 years old he had received a six-month referral order for attempted robbery of a mobile phone.
Convictions followed for threatening behaviour and aggravated vehicle taking, for which he had been given a Youth Rehabilitation Order.
In September 2015 he said he had received an 18-month Youth Rehabilitation Order for four offences of supplying Class A drugs to undercover police officers.
He said he also had a conviction for possessing an offensive weapon, which was a knife, which he said he had on him for his own protection.
The teenager then told the jury he had met the 21-year-old man through Instagram.
He said they would talk about drugs and, within three days of their first contact, it was arranged he would be collected in a car at Dagenham East Railway Station and brought to Watford for the purpose of selling drugs.
The defendant told the jury he was taken to an address in Derby Road, Watford, where he met the 21-year-old man and others.
From that address he said he would deal drugs to “customers” who would come to buy Class A drugs.
The defendant has pleaded guilty along with the 21-year-old man to a charge that they conspired together and with Koy to supply a controlled drug of Class A.
The 21-year-old man has also pleaded guilty to perverting the course of justice by instructing one of the women who was at the flat that afternoon to lie to the ambulance crew about how Koy had received his injuries.
He also told the other girl she should return to the flat and remove any incriminating evidence.
Koy was a former pupil at Queens School, Bushey.