The jury in the Joanna Yeates murder trial has been told that Vincent Tabak could have let her live if he had wanted.
Tabak, a 33-year-old Dutchman, denies murder but admits the manslaughter of the blonde architect on 17 December last year.
But in his closing speech at Bristol Crown Court prosecutor Nigel Lickley QC said he had intended to kill Yeates.
"He knew what he was doing. He was in control and he knew she would die and he held her neck long enough, and coupled with a smothering second hand, to be sure that she would. It goes to his intent and his intention to kill or cause really serious bodily harm," he said.
"He knew she was struggling and fighting, he knew she was in pain, he knew she was frightened, he knew she couldn't breathe.
"Instead of letting go and releasing his grip and letting her live, he carried on and on and on until she went dead in his hands, her life extinguished."
The trial was adjourned until Wednesday when the judge, Justice Field, will begin summing up.
Landscape architect Yeates was reported missing two days later when her boyfriend Greg Reardon returned to their ground floor flat in Canynge Road, Clifton, Bristol, after a weekend away.
Last Thursday the court heard Tabak explain for the first time how he strangled 22-year-old Yeates to death.
As he broke down in tears in the witness box, the defendant told jurors he "still can't believe" he killed his neighbour after he "completely misread the situation" when Yeates invited him in for a Christmas drink.
Tabak said he had been attracted to Yeates and "made a pass at her" when she invited him in to her flat in Clifton, Bristol, describing the university graduate as "flirtatious".
Tabak described his actions following the cover-up of her death as "calculating, dishonest and manipulative" and apologised for putting Yeates' family and her boyfriend Greg Reardon "through hell".
Jurors have been told Yeates suffered 43 separate injuries when she was attacked, and her body was later dumped on a country lane in Failand, North Somerset - just three miles from her flat.
Police launched a massive hunt for the university graduate and her body was found by dog walkers on Christmas morning.
Tabak was arrested on 20 January when police matched his DNA to samples found on Yeates' body and clothing.
The prosecution argue Tabak's assault was sexually motivated - an accusation rejected by the defence.
Nigel Lickley, QC for the Crown, told the jury Tabak made no attempts to resuscitate Yeates, neither did he call an ambulance. Lickley called the defendant "shrewd" and said when the Dutchman had told others Yeates must have been killed by a "crazy" man, he was in fact describing himself.