Computer manufacturer Dell has launched an investigation after a call centre worker told a customer the company "would not deal with Israel".
The male staff member was asked whether a laptop charger could be sent to Israel but responded by falsely claiming the company was boycotting the Jewish state.
A company spokesman said an internal review of the incident had begun and reassured customers that products remained on sale in Israel and to Israeli shoppers online.
Ian Sheratte of Finchley, north London, said he had called the Dell helpline on behalf of his 18-year-old daughter, Corine, after her charger broke. She is currently on a kibbutz in the Negev as part of a gap year in Israel.
Mr Sheratte was hoping to get a replacement under the laptop's warranty.
He said: "I spoke to someone and he said he could not send me a new charger under the warranty because the laptop was out of the country.
"So I asked if I could buy one and I'd send it to my daughter in Israel. He asked me to hold while he went to speak to the manager. Then he came back and said: 'We will not send you one because we do not deal with that country'.
"He said they wouldn't sell it to me on the basis that I'd then send it to Israel. I asked if it was an official boycott and he said 'you could call it that'."
Mr Sheratte said he made his feelings clear to the company when he was later sent an email asking him to complete a customer satisfaction survey.
Dell spokesman James Gibb said: "We would like to apologise to the customer for any inconvenience caused. Dell products are available to buy in Israel and there are no sanctions of any kind in place.
"We are currently reviewing this matter internally with our customer service team to understand the basis for the confusion."
Pro-Palestinian groups have increasingly advocated a boycott, divestment and sanctions campaign against Israel in recent months.
But last November Shaher Saeed, general secretary of the Palestine General Federation of Trade Unions (PGFTU), said his organisation had no policy on BDS.
He said that a boycott would do "more harm than good" to Palestinians.