The Conservative Party accepted a further £5m donation from the businessman Frank Hester days before the general election was called in May.
The donation was taken two months after he was accused of making racist comments about the Labour MP Diane Abbott.
In March, claims emerged that Mr Hester had told staff at a meeting in 2019 that Abbott made him “want to hate all black women” and “should be shot”.
At the time, the then Prime Minister Rishi Sunak said the comments were “racist” and “wrong” but made it clear that the party would not return Mr Hester’s money.
Mr Hester has previously apologised for making “rude” comments about Abbott but said his remarks “had nothing to do with her gender nor colour of skin”.
Responding to the latest donation figures, Abbott told the BBC: “I am shocked that the Tories are taking money from Frank Hester, when even they admitted his remarks were racist.
“It demonstrates that they are not serious about opposing racism and it may also mean they are desperate for money.”
Electoral Commission records, published this week, show that the party accepted the sum from Mr Hester’s Leeds-based healthcare software company, The Phoenix Partnership (TPP), on 17 May.
There is a three-month lag before donations are made public by the commission.
Mr Hester’s £5m donation in May follows £150,000 accepted in March, £5m in January and £10m donated to the party last year, totalling more than £20m since the start of 2023.
According to parliamentary records, he also gifted the prime minster the use of a helicopter for a political visit in November last year, valued at £15,900.
A Labour source said: “The Tories election campaign was funded by cash from a man who made abhorrent, racist comments.
“The Conservatives have offered no apology and they have no shame.
“If the Tories want to show the public that they’ve learnt anything from their staggering election defeat they should start by committing to never taking any money from Frank Hester again.”
Liberal Democrat deputy leader Daisy Cooper called on the Conservatives to hand back all the money Mr Hester has donated because his comments are “racist” and “just as inexcusable and disgusting now as they were then”.
“The Conservative Party should hang its head in shame for taking yet more money from this disgraced donor,” she said.
“They must also rule out any future peerage for Frank Hester — This is someone whose attitudes should have no place in British politics.”
The Conservative Party has been approached for comment.
The total amount of donations accepted by the Conservative Party in the run-up to the election was just over £16m and the Labour Party received just over £26m in donations in that time.
The Electoral Commission’s Jackie Kileen said there £51.6m in donations was accepted by all political parties in the same period, between April and June 2024, which was one of the biggest donation amounts on record for a three-month period.
Ms Kileen said this was more than double the same period in 2023, but “it’s not surprising to see a significant spike in donations in the lead up to a general election”.
