Oscar-winning actor Kevin Spacey has told a jury the sexual assault allegations against him are either “madness”, “make no logical sense”, or are a “stab in the back”.

The Hollywood star became fought back tears as he said his world “exploded” when allegations first emerged against him on the internet in 2017.

He began giving evidence from the witness box at Southwark Crown Court on Thursday, where he said he was “not on a suicide mission” after being accused of “aggressive” crotch grabs.

The 63-year-old told jurors he is a “big flirt” and described his encounters with two of the alleged victims as “comfortable” or “relaxed”, while insisting “nothing happened” with a third.

He denies charges including sexual assault and indecent assault, which are alleged to have been committed between 2001 and 2013.

Spacey said an aspiring actor’s claims that he drugged him and performed a sex act on him while he was asleep in his flat were false, saying the pair had shared an “intimate moment”.

Asked about his initial reaction the accusations, the American Beauty and House Of Cards star said: “My initial reaction to that was this is somebody who is just shaking me down.”

The defendant also described his relationship with a man who drove him to a lavish showbiz party in the early 2000s as “somewhat intimate”, but denied assaulting him in a “violent, aggressive, painful way”.

As well as describing allegations by a man he met in a West End theatre in the mid-2000s as “madness”, he told the jury that claims he directed a “barrage of vile comments” at him were words he had “never said… to anyone in my life”.

Addressing sexual grab claims made by a fourth complainant he met in a pub near Oxford, he said he had “primarily” no issue with what the man had told the court, adding: “I made a pass and I’m only happy that he testified that the moment he told me he was not interested I stopped.”

Spacey is accused of having had a “panicked” look on his face after a man rejected an alleged sexual grab at an expensive property he was staying at in the Cotswolds in the early 2010s – to which he said he did not remember a “great deal” about the evening.

The actor was seen dabbing his eyes with a tissue and could be heard sniffing as he gave evidence about his “lost reputation” from the witness box.

Telling the court about the first allegations that emerged against him online, Spacey said: “There was a rush to judgment and before the first question was asked or answered I lost my job, I lost my reputation, I lost everything in a matter of days.”

He also told jurors he felt pressurised to come out as gay after allegations of sexual misconduct were first levelled at him.

During his evidence, Spacey gave jurors an insight into his relationship with famous faces – including storing “the most expensive Mini Cooper” in Sir Elton John’s garage and gifting a ping pong table to Dame Judi Dench.

Denying the allegations against him made by the man who claimed Spacey had almost made him “come off the road” due to a “painful” crotch grab, the defendant told the jury: “He was a lads’ lad. He was funny and charming and flirtatious.”

Spacey said he touched the complainant in “romantic” and “intimate” ways.

He said he and the alleged victim did not take things further because the man “made it clear that he did not want to go any further and that happens at times and you just respect how far someone wants to go”.

Spacey said: “I can’t remember specific conversations we had but I remember the tone, I remember the atmosphere, I remember the laughter.

“We had a very fun time together.”

The actor accepted touching the man but said: “It did not happen in a violent, aggressive, painful way.

“It was gentle … and it was in my mind romantic.”

Asked by his barrister if there was any reluctance from the alleged victim to his advances, Spacey said: “No. The only thing he made clear is he did not want to go any further than we were going and I respected that.”

Questioned whether the man had said anything after Spacey had touched him, the defendant said: “I think he said things like ‘this is new for me’ so I think that he may have been surprised by his reaction.”

The actor denied he had almost made the complainant “come off the road” after the alleged “aggressive” grab, saying: “That never happened. I was not on a suicide mission.”

Asked how he felt after the alleged victim made allegations against him, the defendant said: “I was crushed.

“I never thought that the (man) I know would (so many) years later stab me in the back.”

Mr Gibbs then asked Spacey about the man he allegedly met in a West End theatre.

Questioned on why he believed the allegations to be “madness”, the actor said: “It never happened.”

Asked to respond to the man’s allegations of “vile comments”, the Hollywood actor said: “I never said any of the things that he claims I said to him and wouldn’t and never have to anyone in my life.”

He told the jury that he did not recognise the complainant “at all” when showed a photograph of him.

Asked what he remembered of that day, Spacey said: “Not a great deal.”

Detailing his account of what happened with the aspiring actor in the late 2000s, the Hollywood star told the jury that he “hurriedly left” after the pair shared an “intimate moment”.

Spacey said: “We had had a sexual encounter after which I had gone to the bathroom and I came back from the bathroom and it was like… something had changed.

“The person that I had this intimate moment with was suddenly awkward and fumbling… and I don’t want to say ran out… but hurriedly left. And it felt very odd.

“I felt like maybe he was making an excuse and it concerned me and my memory is… that I called this person to make sure they were OK… and they were OK.”

Asked what he remembered of the alleged encounter, Spacey said: “I remember the end of the evening and that was what struck me in my mind because we had a consensual and, I believe, a very nice and lovely evening.

“If he regretted it immediately I don’t know, I can’t speak for him, but something was odd – it was strange.”

Questioned on whether he remembered any physical contact he had with the man, Spacey told jurors: “I don’t remember but I know the way I am with someone and I would never be behaving in the way he claimed – it makes no logical sense.

“I think we were very comfortable with each other.”

He said he did perform a sex act on the man but claimed it was consensual.

The defendant, standing trial under his full name Kevin Spacey Fowler, was labelled a “sexual bully” when proceedings began last month.

The 63-year-old denies charges including sexual assault and indecent assault, which are alleged to have been committed between 2001 and 2013.

Spacey pleaded not guilty in January to three counts of indecent assault, three counts of sexual assault and one count of causing a person to engage in sexual activity without consent.

The two-time Academy Award winner also previously denied four further charges of sexual assault and one count of causing a person to engage in penetrative sexual activity without consent.

The trial continues.