Elton John gives evidence by videolink at Kevin Spacey's London trial

Singer Elton John appeared by videolink in a London court on Monday to give evidence at Oscar-winning actor Kevin Spacey's sexual assault trial.

Spacey, 63, has pleaded not guilty at London's Southwark Crown Court to 12 charges of sexual offences allegedly committed against four men in Britain between 2001 and 2013.

The offences allegedly took place at a time when he was mainly living and working in Britain, including from 2003 as artistic director of the Old Vic theatre in London.

Read | Kevin Spacey denies sexual assault charges in UK court

The four accusers have said Spacey aggressively groped them and, in the case of one complainant, performed oral sex on him while he was passed out in Spacey's flat, which Spacey last week said was "completely wrong and upsetting".

The two-time Academy Award winner on Monday called John as a witness, with the British singer appearing by videolink from Monaco.

John was asked about Spacey's attendance at a lavish party hosted by the singer in the early 2000s, on the way to which Spacey is alleged to have sexually assaulted a driver so aggressively he almost crashed the car.

John said Spacey stayed overnight at his and his husband's home in Windsor after the event, but said: "I can't remember him coming down after that."

He was also asked by prosecutor Christine Agnew about a photo which showed the complainant outside a London theatre as John left the venue on another occasion a few years later.

John said he did not recognise the man and would not have noticed him at the time as it was "always a mad rush" to get to his car when he left a venue with photographers outside.

"They could be the queen and I don't notice," he said.

John's husband, David Furnish, also gave evidence by videolink from Monaco, saying that Spacey had only attended a party they staged annually at their home in 2001, a few years earlier than the accuser had stated in his evidence.

Furnish said he had occasionally spoken to the complainant, who he described as a "very friendly, affable, easy-going person".

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"You could always engage in playful banter with him," Furnish said. "He was a good, fun, engaging person."

The man has told the court Spacey made increasingly unwanted sexual advances which had left him feeling physically sick, while the actor said they had enjoyed a consensual, "romantic" relationship.

Furnish told the court he remembered asking the complainant "how is the most handsome driver in London?", adding: "He was always very comfortable with those types of exchanges."