South Africa's ambassador to China has according to state media compared Nelson Mandela to Mao Zedong, the Communist leader whose rule saw tens of millions killed by famine and the chaos of the Cultural Revolution.

"They were both very strong leaders who fought for the liberation of their people, and who also contributed to laying the foundation for further development in society," South African ambassador Bheki Langa was quoted as saying by China's official news agency Xinhua.

He added that Mandela, whose death was mourned Tuesday in Soweto by dozens of world leaders -- not including China's President Xi Jinping -- "valued the contribution the Chinese people, government and Party had made in ending the obnoxious system of apartheid in South Africa".

Xinhua headlined its report: "Mandela, Mao shared similarities: S. Africa ambassador".

In the West, Mao's legacy is principally associated with the Great Leap Forward, the late-1950s industrialisation campaign that triggered widespread starvation, with academic estimates as high as 45 million deaths, and the Cultural Revolution, a bloody and turbulent social upheaval during the 1960s and 70s which remains a sensitive topic in the country.

Mandela won the Nobel Peace Prize and is widely hailed as an emblem of reconciliation for his role in South Africa's transition to democracy.

A South African embassy spokeswoman declined to elaborate on Langa's comments.

China and South Africa have stepped up their economic ties in recent years, and Pretoria has twice denied the Dalai Lama -- the exiled Tibetan spiritual leader condemned as a separatist by Beijing -- a visa.

Within China, supporters of Mao tend to focus on the late leader's earlier revolutionary years, including his role in the 1949 founding of the People's Republic.

President Xi has sought to capitalise on the sentiment by invoking Maoist doctrine in some of his rhetoric, and Chinese authorities are reportedly spending billions of dollars on celebrations of the 120th anniversary of Mao's birth on December 26.

In the days since Mandela's death, Chinese state print and broadcast media have run reports highlighting the late South African leader's praise of Mao.

But Mandela's remarks seem to have focused on Mao's military tactics during China's civil war rather than on his legacy as China's leader.

In his 1994 autobiography "Long Walk to Freedom", Mandela hailed Mao's "determination and non-traditional thinking" in leading the Communists to victory, which he read about in American journalist Edgar Snow's seminal book on the Chinese leader.

In an interview with Time magazine's Richard Stengel, Mandela praised Mao's military tactics during the Long March, which he described as "a miracle".

He added that Snow was "not a communist" and had an "advantage because he could also criticise" Mao.

During the struggle against apartheid the Chinese Communist Party supported the Pan Africanist Congress, a rival to Mandela's Moscow-backed ANC, and it was not until 1998, four years into his presidential term, that diplomatic ties between the two were established.