The British millionaire accused of murdering his glamorous bride on their honeymoon today told his murder trial: I am controlling, intense and bisexual, but I did not kill my wife.

Shrien Dewani today formally entered not guilty pleas at the Western Cape High Court in South Africa today, nearly four years after his wife Anni Dewani was gunned down as the pair toured a rough neighbourhood in Cape Town.

Dewani, 34, denied any involvement in plotting to kill his wife, who died from a gunshot wound to the neck.

Graphic footage of the crime scene and the prone body of Mrs Dewani was played to the court - which included members of both families - as the suspect admitted sexual activity with male prostitutes and a history of arguments with his wife during their 18-month romance.

The care home entrepreneur, from Weston-on-Trym near Bristol, had to be extradited to South Africa to face trial against a background of lurid allegations about his private life.

Today, for the first time publicly, Dewani described himself as bisexual and lifted the lid on the behaviour that characterised their relationship.

He also recalled the final words he said to his 28-year-old wife, the last time he saw her alive as car-jackers struck during their luxury honeymoon in November 2010.

Prosecutors argue that Dewani - who was extradited from the UK to face trial - conspired with locals Zola Tongo, Mziwamadoda Qwabe and Xolile Mngeni to kill his wife.

Tongo, Qwabe and Mngeni are already serving jail terms in connection with the murder.

Dewani's counsel, Francois van Zyl, said the trauma of the incident has affected his client's ability to remember things clearly - but insisted he was not responsible for plotting the murder.

Reading from Dewani's hour-long witness statement, Mr van Zyl described how Dewani and his wife had been in the back of Tongo's taxi when they took a turn off the motorway into a township.

Dewani said: "The next thing I remember was banging noises coming from the front and right-hand side of the car. There was a lot of shouting in a language I did not understand.

"The next thing I recall is somebody next to me, who told me to lie down. The person had a gun in his hand.

"He was waving the gun in the air."

Mr van Zyl said the gunman told the defendant to "Look down! Lie down!"

Dewani said: "We were both terrified and immediately complied with his demands. I was lying half on top of Anni. Another person was behind the steering wheel. I do not know where Tongo was at that stage."

Dewani said he pleaded with the attackers to let him and Anni go, but they demanded Dewani's phone.

The defendant said: "He searched me and found my phone in my trousers. He got angry. He placed the gun against my left ear and said words to the effect that I should not lie to him or he would shoot me.

"I heard a clicking noise from the gun which scared me even more. I have never been close to a real gun before."

Dewani's statement said they returned to the motorway with another driver taking control of the wheel.

He said Anni was screaming, and he was ordered to keep her quiet as they drove on to another side road.

Dewani said: "The driver said that they were not going to hurt us, they just wanted the car and they were going to let us go separately. I begged them to let us go together."

Dewani said he was ordered to leave the car with a gun to his head.

"The last thing I had said to Anni was to be quiet and not to say anything."

The next day, Dewani was informed that his wife had been found dead.

"At that point, my whole world came crashing down," he said.

"The next thing I recall is that the doctor gave me some pills in my bedroom."

There were gasps at the Western Cape High Court in Cape Town as police footage of his wife's body was shown.

Dewani, wearing a black suit, white shirt and dark tie, appeared to bow his head as forensics officers were seen opening the door of the abandoned taxi, showing a bloodstained Anni dead on the back seat, her long dark hair billowing in the gentle breeze.

As the camera panned to the other side of the car, the court saw blood covering her ankles and feet.

Pathologist Dr Janette Verster said Mrs Dewani, who grew up in Sweden, suffered gunshot wounds to her left hand and her neck - the latter being the likely cause of death.

The fatal shot was delivered "at close range", with a suggestion that Mrs Dewani might have been grabbing on to "someone or something" at the time she died, the court heard.

Dr Verster added there was no suggestion the victim had been sexually assaulted.

Dewani denies murder, conspiracy to commit kidnapping, robbery with aggravating circumstances, kidnapping, and defeating the ends of justice.

With his jet black hair greying, he stood and calmly addressed the court and judge Jeanette Traverso, saying: "I plead not guilty to all five counts, my lady."

Dewani's witness statement also said: "My sexual interactions with males were mostly physical experiences or email chats with people I met online or in clubs, including prostitutes."

He said both he and his wife - previously known as Anni Hindocha - were "opinionated and liked to control every detail" but that they loved each other.

They began dating in summer 2009, although the relationship cooled and at one point ended before they rekindled their romance in March 2010.

The couple married later that year in Mumbai and honeymooned in Cape Town.

Members of the victim's family wore brooches with Anni's face on as they attended the hearing today.

Before his extradition, and between months of court hearings, Dewani was detained in a hospital in Britain with depression and post-traumatic stress disorder.

It is not yet known whether he will be giving evidence in his defence.

The case, which is due to run until December, was adjourned until Wednesday morning.