A 13-year-old Israeli girl has described her shock after a Jewish academic refused her request for help with a school project “until there is peace in Palestine”.

Shachar Rabinovitch said she had been excited to email Marsha Levine, a former Cambridge University expert with more than 40 years of experience working with horses.

But the girl’s enthusiasm turned to shock when Dr Levine replied that she would only answer questions about the animals “when there is peace and justice for Palestinians in Palestine.”

The academic, a member of the Jews for Justice for Palestinians group, later claimed “the Jews have become the Nazis” and said she would not help Shachar because she came from a country whose prime minister “wanted ethnic cleansing”.

The teenager said she was shocked to discover “that Jewish people could hate Jews in Israel”.

“It was new to me,” she explained. “I was kind of shocked and a bit angry. She could have answered differently or not responded at all.”

Shachar told the JC on Wednesday that she had emailed Dr Levine after reading an article online about her studies of horses.

She said: “The response confused me. I did not know what Jews for Justice for Palestinians was. She told me she was a member and supported BDS. I did not want to get into that with her. I did not argue with her, I just said thank you.

“I think every person has a right to their own opinion, but there is a line you should not cross when talking with a 13-year-old girl who only asks about horses.”

Shachar, who takes part in after-school show-jumping classes, said she was surprised when friends told her the email exchange had made headlines around the world.

The girl, who lives on a kibbutz near Pardes Chana, said: “I did not want this to be a big deal. I feel bad if Dr Levine gets bad emails from people.”

On Tuesday, Dr Levine said she was not embarrassed by her response to the girl and had believed it was “fair” not to help her. She said Jews had “turned themselves into monsters” in their treatment of Palestinians in Gaza.

The archaeozoologist had received the email from Shachar last week. The girl had written: “I know you are a very important person and I've read your article about horses (Domestication, Breed Diversification and Early History of the Horse) and I love horses very much and it will be an honour if you will answer my questions.”

She went on to ask about breeding patterns and the use of horses by humans in ancient times.

Dr Levine replied: “I'll answer your questions when there is peace and justice for Palestinians in Palestine.

“I am a member of Jews for Justice for Palestinians. I support boycott, divestment, sanctions. You might be a child, but if you are old enough to write to me, you are old enough to learn about Israeli history and how it has impacted on the lives of Palestinian people.

“Maybe your family has the same views as I do, but I doubt it.”

Dr Levine concluded by suggesting the schoolgirl read a JfJfP piece about the history of the Israeli-Palestinian conflict.

The American former academic defended her response. She said: “I didn’t ask her to email me. I don’t know how she got my email address. I can do whatever I want. I didn’t invite her to email me. If she wanted to read anything I had written she could find it on the internet.

“I made the decision that I have the choice not to waste my time on people who tread on the rights of other people. I didn’t do anything to her. I said that when there is justice for Palestine I will answer her – that’s a fair answer. I’m a signatory to Jews for Justice for Palestinians and I sent her a link. I did it as a matter of conscience. The way Israel treats Palestinians is totally disgusting.”

Dr Levine said she wanted the teenager to stand up to violence when she grows up.

“The violence against Palestinians never stops. The people who live in Gaza cannot get education, health, water. What does it say about Jews that they support that? Jews have turned themselves into monsters.

“I want this girl not to worry about horses. I don’t need people emailing me. I’m not an academic anymore. My research was all in the past. I’m doing other things now. I don’t see any obligation to further her ego or make her feel better about herself. I don’t think it’s about her – I think it’s about her parents.

“I gave her useful information which might help her for the rest of her life. I have to stand up for what I believe in.

“Benjamin Netanyahu wants ethnic cleansing. The Jews have become the Nazis. Jews are behaving just like the people who treated them. It’s not all Israelis or all Jews.

“It’s really fascinating that the JC and the people behind it claim they speak for Jews. You don’t speak for me. Never once was I quoted correctly in the past, not even about the bloody horses. I want justice for Palestine.”

Shamir Rabinovitch, Shachar’s father, said he believed children were “out of the equation” when discussing the Israeli-Palestinian conflict.

He said: “For me, as long as a kid is not holding a knife, a rock, or justifying violence, they are just a kid and I need to help him regardless of what his parents do or think.

“This is why I was so angry from this response to the mail my girl sent. I never pushed extreme ideas to her head and I will never do that to anyone else.

“Political arguments are something that should be conducted by adults. Boycotting a 13-year-old girl just to prove something is no better than not treating some kid in an Israeli hospital just because his father is a terrorist. Kids for me are out of the equation.”

Board of Deputies president Jonathan Arkush said: “Dr Levine fits the description of the typical boycotter: blinkered, bigoted and thoroughly unattractive and unpleasant.”

The Fair Play Campaign, which opposes boycotts, said: “We have always said that boycotts of Israel lead to racist discrimination against Israelis. This incident is yet more proof that we were right. Harassing a schoolgirl just because she's Israeli is both nasty and pointless, but it is exactly the kind of behaviour we've come to expect from the morally-bankrupt BDS campaign."

JfJfP distanced itself from Dr Levine, saying it was “self-evident we cannot and do not approve of her awful response to the 13-year-old’s enquiry”.

A JfJfP spokeswoman said: "The refusal of Dr Levine to engage with this individual Israeli does not represent JfJfP policy. We believe strongly that children - Jewish and Palestinian - should be treated as children. Certainly, no child is responsible for the actions of the state in which it lives."

The group said it did not support a "blanket boycott" of Israel, but a "smart boycott" of against institutions and organisations "undermining" the Palestinian people.