John Allan said there has been a shift away from white men after millennia of bias in their favour - despite the group overwhelmingly holding the top positions, the Press Association reported.
Allan later said the comments, made the day after International Women’s Day, were “humorous” and a “rather colourful turn of speech” used to encourage an audience of budding business people.
Speaking at the Retail Week Live conference on Thursday, he said: “If you are female and from an ethnic background and preferably both then you are in an extremely propitious period.
“For a thousand years men have got most of these jobs, the pendulum has swung very significantly the other way now and will do for the foreseeable future I think.
“If you are a white male – tough – you are an endangered species and you are going to have to work twice as hard.”
Three of Tesco’s top team are women and eight are men.
There are no full-time female executives on Tesco’s board, according to the Guardian.
Women are still poorly represented on the boards of FTSE 100 companies.
Last year, Carolyn Fairbairn, the director-general of the CBI, said fewer than 10% of their executive directors are women and described the aim to raise this to 25% as “ambitious”.
After the London event, Allan told The Guardian: “The context was (that) I was talking to a bunch of aspiring non-executive directors, many of whom were women, and I wanted to give them some encouragement and, therefore, I used that rather colourful turn of speech.
“It was intended to be humorous, a bit hyperbolic. Clearly, white men are not literally an endangered species but I was actually wanting to make the reverse point, which is that it is a great time for women and people of ethnic minorities who want to get on in business.”