Dozens of Democrats have moved quickly to sever ties with Harvey Weinstein, with many donating his campaign contributions to women’s charities, as more allegations of sexual harassment emerged.

The Senate minority leader, Chuck Schumer, said he would donate $14,200 received from the Hollywood producer to women’s charities. Another senator, Kristen Gillibrand, said she would give $11,800 to a sexual assault victims group and hit out political critics seeking to embarrass her with the link to Weinstein.

A spokesperson for Gillibrand said: “Kirsten invites the rightwing activists using this terrible story as a political tool to join her in actually working to combat sexual assault and sexual harassment in our society.”

Weinstein has given more than $1.4m in political contributions since 1992, virtually all to Democrats.

In an extensive report by the New York Times last week, it was alleged that Weinstein had reached at least eight settlements with women he had sexually harassed, and that he would invite women to his hotel room under the guise of work and then greet them naked or ask them to massage him or watch him shower.

Among Weinstein’s accusers are the actors Ashley Judd and Rose McGowan, the latter of whom allegedly reached a $100,000 settlement for an incident of misconduct that happened when she was starring in Scream.

On Saturday Donald Trump waded into the scandal, telling reporters at the White House: “I’ve known Harvey Weinstein for a long time. I’m not at all surprised to see it.”

More allegations against Weinstein emerged over the weekend. Liza Campbell, a British artist and writer, alleged that he had asked her to join him in the bath. A TV reporter said Weinstein had masturbated in front of her, and a waitress who worked at a restaurant in Weinstein’s office said she had witnessed him dining with and being inappropriate towards a succession of young women.

Campbell told the Sunday Times that she had gone to see Weinstein at the Savoy hotel to discuss film scripts when he disappeared into the bathroom and then asked her to “jump in the bath” with him.

She said he then called out to her: “Come on, it’ll be fun. We can drink champagne. You can soap me – whaddaya say?” Campbell said she tried to leave the hotel room but two of the doors were locked, and it was only after she found a third door that she was able to leave.

Senator Elizabeth Warren, who has been tipped as a possible 2020 presidential nominee, said she was donating $5,000 received from Weinstein to Casa Myrna, a charity that fights domestic violence. Others Democrats who followed suit included the senators Patrick Leahy, Martin Heinrich, Cory Booker, Al Franken, Bob Casey and Richard Blumenthal.

Weinstein was key in influencing other Hollywood heavyweights to make political donations, and he contributed substantially to Barack Obama and Hillary Clinton’s campaigns.

The Democratic national committee has received almost $250,000 from him over the past two decades. It announced it would be contributing the $30,000 Weinstein had given this year to organisations that promote women in politics, but it was criticised for not donating the total of all Weinstein’s contributions over the years.

Weinstein’s allegedly inappropriate behaviour towards women he worked with and those who starred in his films has been referred to as an open secret in Hollywood.

Jade Budowski, who worked at the Tribeca Grill in Weinstein’s company’s office, told the New York Post she had witnessed him with “a string of young women, some seemingly no older than 21,” who she said “entered the restaurant for long, flirty dinners with him”,

Budowski said there had been an unspoken rule that he was not be disturbed when dining with these women and that “after dining, Weinstein and a woman would often disappear for a while, exiting the restaurant through a side door”.

In another account, Lauren Sivan, a TV journalist, alleged that Weinstein had once cornered her in a restaurant kitchen, and, when she refused his sexual advances, masturbated in front of her.

Weinstein has expressed regret for his inappropriate behaviour towards women stretching back decades, saying “I own my mistakes”, but his lawyers say he also denies many of the allegations made against him. Weinstein has taken a leave of absence from his company as internal allegations are investigated.