An eighth woman has come forward with claims that former US president George HW Bush groped her.
The unnamed interpreter claims Mr Bush touched her inappropriately in 2004.
The alleged incident took place at a meeting between the former president and the Spanish defence minister Jose Bono Martinez.
The interpreter has not previously spoken publicly about the incident.
"It was 2004," she said. "Spanish troops had been withdrawn suddenly from Iraq and I was working as an interpreter in Spain."
Recently elected Socialist Spanish Prime Minister Jose Zapatero had sent Mr Martinez to Mr Bush with a gift of a pair of hunting rifles, when Mr Bush's son was nearing the end of his first term as President.
The interpreter would not disclose the contents of the meeting, citing confidentiality concerns. Media reports suggest Mr Martinez was hoping to enlist Mr Bush's help in establishing greater communication between the US president and the Spanish prime minister.
'He grabbed my bum'
"When the time came to take the photos, Mr Bush insisted on me being in the photo," the interpreter said.
"I remember thinking this was odd. Usually we stay outside of the frame.
"He grabbed my bum. At first I thought it was an accident, but then he did it a second time."
Her story is similar to other allegations made against Mr Bush. Another woman, Roslyn Corrigan, told Time magazine that Mr Bush touched her inappropriately in 2003, when she was 16. On Thursday, CNN reported allegations from a 55-year-old woman who said Mr Bush touched her inappropriately in April 1992.
In October, a spokesman for Mr Bush, Jim McGrath, acknowledged that Mr Bush had "on occasion ... patted women's rears in what he intended to be in a good-natured manner".
Mr McGrath partially blamed Mr Bush's use of a wheelchair. "His arms fall on the lower waist of people with whom he takes pictures," he said.
The interpreter said Mr Bush had been standing during the alleged incident. Mr Bush did not start using a wheelchair until around 2012, roughly eight years after the interpreter says the incident took place.
'He knew I couldn't say anything'
"He was not in a wheelchair at the time. We were standing in front of a fireplace," she said.
"I was angry more than upset, but I couldn't say anything in the circumstances. I remember thinking at the time that he's doing this because he knows I can't say anything.
"How could I create a scene with a minister present when the atmosphere was already tense following the withdrawal of troops by a socialist government?"
Though she had experienced sexual harassment both before and after the incident, it remains the only time she has experienced it at the hands of a politician.
"When I got home that night, I remember telling my kids," she said.
"I happened to comment on it to a colleague and she said the same thing had happened to her. In fact, when articles were published last month she sent me one of them, asking if it sounded familiar.
"I didn't think about it for a long time. Now people are speaking out about it, it's brought all these things flooding back."
It was her daughter who prompted her to contact the BBC, when she sent her the article about Ms Corrigan's allegations.
"I got really angry," she said. "Photo ops obviously were, or are, his modus operandi. I was there because I was a trusted interpreter. I was extremely professional. He was not.
"Who do the men who do these things think they are? I kind of think it's a duty now to speak out."
Mr Bush's spokesman has not responded to requests to comment on the latest allegations. But on Monday, in response to Ms Corrigan's accusation, Mr McGrath told the BBC that Mr Bush "simply does not have it in his heart to knowingly cause anyone harm or distress, and he again apologises to anyone he may have offended during a photo op".