The White House is willing to set up a call for rapper Nicki Minaj about the safety and effectiveness of the coronavirus vaccine after she said she wanted to do more research on vaccines before getting one.

"As we have with others, we offered a call with Nicki Minaj and one of our doctors to answer questions she has about the safety and effectiveness of the vaccine," said a White House official.

Minaj had said in a tweet that she had not been able to complete enough research of her own on the Covid-19 vaccines to get one in time for the Met Gala, a star-studded fundraiser for New York's Metropolitan Museum of Art.

Later, Minaj added that she will get vaccinated to be able to tour.

Trinidad-born Minaj sparked an international furor when she alleged on Twitter that her cousin in Trinidad refuses to get a vaccine because his friend became impotent after being vaccinated.

"His testicles became swollen. His friend was weeks away from getting married, now the girl called off the wedding," said Minaj, who has 22.6 million Twitter followers.

Latest coronavirus stories

The comments triggered an international backlash, with senior US and British coronavirus officials condemning the claims.

Trinidad and Tobago Health Minister Terrence Deyalsingh criticised the claim as "false".

Britain's health minister Sajid Javid issued an appeal to people in the public eye not to spread "untruths" about the Covid vaccines after the chief medical officer for England, Professor Chris Whitty, took issue with Minaj's claims.

At a Downing Street press conference on Tuesday, Prof Whitty said such claims were "clearly ridiculous" and were "designed just to scare".

He said people who were deliberately "peddling untruths" about the vaccines should be "ashamed".

Asked about Minaj's comments, Mr Javid said: "I do know who she is but I don't want to focus on a particular individual. I don't want to give the oxygen of publicity they are probably craving for by making such comments.

"Anyone, whether you are a pop celebrity, a footballer or a politician, you should be very careful about your language.

"Certainly when it comes to something as lifesaving as vaccines - in this country there are 112,000 fewer deaths, we estimate, because of our vaccine programme - they should be really careful about what they say and not spread untruths."