The 87-year-old entertainer is on trial at Southwark Crown Court on four indecent assault charges involving three women who accuse him of groping them when they were teenagers in 1971, 1978 and 1983.
The woman's testimony came after the judge told the jury she had approved an application for bail allowing Harris to be released on Friday from Stafford Prison where he has been serving time for previous convictions from 2014.
Former TV star Rolf Harris will be set free from prison tomorrow while still fighting child sex abuse charges, a court heard today.
Harris has been attending the current trial via video-link but, after being released, will attend his trial in person.
The jury was not told why he was in prison. The ages of the girls, at the times of the alleged assault, range from 13-years old to 16.
The woman said that after the screening the children were invited to a room where Harris came up beside her at a drinks table.
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The woman did not make an official complaint until July 2014 but told the court she had informed friends and work colleagues of Harris' assault on her in the intervening years.
He then asked her: "Do you often get molested on a Saturday morning?", it is said.
Harris is accused of indecently assaulting three teenage girls in the 1970s and 1980s.
The victim later told police the incident left her "shocked and traumatised", but that she did not confide in detectives until 2014 because she was anxious she would not be believed, the court heard. Harris has denied all charges.
"I told him to f*** off and leave me alone", she told the court.
The trial, which opened on May 15, will not sit on Friday.
"I did tell her what happened. she looked shocked - not at what happened but rather, "that's Rolf Harris, don't be silly".