Conservative leader David Cameron has condemned Margaret Thatcher's policy on South Africa during apartheid.
In what some are already dubbing his clearest breaking of ties with the Thatcher years, he wrote in today's Observer that she had been wrong to label Nelson Mandela's African National Congress (ANC) "terrorists" after controversially refusing to support sanctions against the apartheid regime in the 1980s.
Mr Cameron also believes the Conservatives can learn from the mistakes made during Lady Thatcher's era.
"The mistakes my party made in the past with respect to relations with the ANC and sanctions on South Africa make it all the more important to listen now," he wrote.
"The fact that there is so much to celebrate in the new South Africa is not in spite of Mandela and the ANC, it is because of them - and we Conservatives should say so clearly today."
Mr Cameron met Mr Mandela last week during a visit to Johannesburg and described him as "one of the greatest men alive".
And the shadow education secretary, David Willetts, has defended his party leader's decision to disown Margaret Thatcher's South African policies.
Speaking on BBC One's News 24 Sunday programme, Mr Willetts explained what had motivated his leader into making such stark statements.
He said: "David has been to South Africa and was personally incredibly impressed by Nelson Mandela, and he came back clearly aware that there was a specific issue of the approach that we took to Nelson Mandela and apartheid that he needed to tackled."
But Mr Willetts was keen to stress how Lady Thatcher remained a key factor of modern British conservatism, saying her reforms to the economy remained "fundamental".
Lord Tebbitt, the party's former chairman has defended Lady Thatcher's stance due to the political context.
He told the Observer: "Because of his age, Mr Cameron is looking at these events as part of history.
"Others of us who lived through them and had input into the discussions at the time see things very differently. The policy of the Thatcher government was a success."
Lady Thatcher, supported by US president Ronald Reagan, supported a policy of "constructive engagement" with Pretoria to lead to a reform on a government they perceived as being radicals.
In 1987, she said anyone who believed the ANC would ever rule South Africa was "living in cloud-cuckoo-land".