Photograph: Justin Lane/EPA

The presidential candidate Michael Bloomberg has insisted he is a “champion for women in the workplace”, after the republication of a 30-year-old booklet purporting to contain his “Wit and Wisdom” cast an uncomfortable spotlight on the billionaire former New York mayor.

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The Washington Post made the 1990 booklet available online as it published an investigation of how Bloomberg has “for years battled women’s allegations of profane, sexist comments”. The booklet was presented as a gift to Bloomberg on his 48th party and contains a catalogue of sexist remarks attributed to the billionaire during his time at the company he founded.

The renewed attention on Bloomberg – who has for years been the subject of allegations that his company fostered a hostile and sexist environment towards women – comes as he has surged in the race for the Democratic nomination to face Donald Trump in November.

With the leftwinger Bernie Sanders climbing in national polls and former vice-president Joe Biden falling away, Bloomberg’s self-financed candidacy has begun to attract support from moderates seeking what they believe will be an electable alternative to Donald Trump.

On Saturday the rightwing Drudge Report website caused a stir when it said “sources close to the Bloomberg campaign” said he was considering Hillary Clinton, the Democratic candidate beaten by Trump in 2016, as his running mate this year.

But with such increasing prominence, fuelled in part by a massive TV and Facebook advertising effort, has come increasing scrutiny of the former Republican’s record in office and his comments and views.

In one comment printed in the 1990 booklet, the businessman turned politician is said to have said of Britain’s royal family: “What a bunch of misfits – a gay, an architect, that horsey faced lesbian, and a kid who gave up Koo Stark for some fat broad.”

The tone of the comment – seemingly about Prince Edward, Prince Charles, Princess Anne and the scandal-ridden Prince Andrew – is typical of a booklet which a female aide presented when Bloomberg, now 78, was celebrating his 48th birthday.

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Of the Bloomberg Terminal, the computer system on which a fortune estimated at $60bn was built, Bloomberg is quoted as saying: “It will do everything, including give you a blowjob. I guess that puts a lot of you girls out of business.”

He is also quoted as comparing “a good salesperson” to “the guy who goes into a bar, and walks up to every gorgeous girl there, and says, ‘Do you want to fuck?’ He gets turned down a lot – but he gets fucked a lot, too!”

Attempts to contact Buckingham Palace for comment were unsuccessful.

The Post said Bloomberg declined to be interviewed. A spokesman was quoted as saying: “Mike openly admits that his words have not always aligned with his values and the way he has led his life and some of what he has said is disrespectful and wrong.

“Mike simply did not say the things somebody wrote in this gag gift, which has been circulating for 30 years and has been quoted in every previous election Mike has been in.”

In September 2001, however, when Bloomberg first ran for mayor in New York, a position he would fill for three terms, the New York Daily News quoted a spokesman as saying: “Some of the things he might have said. He says he can’t recall saying many of the things he was asked about.”

Bloomberg was also reported to have called the remarks a “bunch of Borscht Belt jokes”.

The publication of the booklet comes during a Democratic primary influenced by the #MeToo movement, which seeks redress against men in positions of power accused of mistreating women.

Trump has enraged opponents with offensive remarks about women and minorities, as well as his history of accusations of sexual misconduct and assault.

Bloomberg has been taken to court by a number of female employees. “A number of the cases,” the Post said, “have either been settled, dismissed in Bloomberg’s favour or closed because of a failure of the plaintiff to meet filing deadlines.

“The cases do not involve accusations of inappropriate sexual conduct; the allegations have centred around what Bloomberg has said and about the workplace culture he fostered.”

The Post report also quoted a witness as saying Bloomberg told a female employee who was pregnant to “kill it”, a claim his spokesman denied.

On the campaign trail, Bloomberg has faced criticism from the Massachusetts senator Elizabeth Warren for refusing to release female former employees from non-disclosure agreements.

In January, the billionaire told ABC News: “You can’t just walk away from it. They’re legal agreements, and for all I know the other side wouldn’t want to get out of it.”

“We can always do better,” Bloomberg said, adding: “I can parade out a whole bunch of any group that you want that will tell you [the company is] a great place to work.”

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On Saturday, accompanying the release of a video of testimonials from female employees, Bloomberg said on Twitter: “I would not be where I am today without the talented women around me. I’ve depended on their leadership, their advice and their contributions. As I’ve demonstrated throughout my career, I will always be a champion for women in the workplace.”

In a statement to the Post, Patricia Harris, Bloomberg’s campaign chair, said: “In any large organisation there are going to be complaints – but Mike has never tolerated any kind of discrimination or harassment, and he’s created cultures that are all about equality and inclusion.”

In the 1990 booklet, Bloomberg is quoted as saying: “Whenever my wife catches me eyeing some broad, she’s very careful to turn to me and say ‘That’s the most expensive piece of ass in the world!’”