Image copyright Getty Images Image caption Mao Zedong, pictured here in 1963, was an avid reader of classical literature

A collection of handwritten notes by Mao Zedong, the founder of modern China, has been sold at auction for 10 times its estimated price.

The notes, written in 1975 to a professor who had been hired to read to Mao, were sold at Sotheby's in London for £704,750 ($910,000).

The auction house said the manuscripts were of the "utmost rarity".

The notes relate to classical Chinese literature and poetry, something the Chinese leader was known to enjoy.

They were written the year before Mao died, as his health deteriorated.

His sight was failing and he struggled to read, so requested the presence of a literary expert to read to him.

A scholar, Di Lu, was found, and the two began meeting. But because Mao was having trouble articulating words, she asked him to write his thoughts down on a notepad to ease communication.

The notes were the product of these meetings and offered, Sotheby's said, "numerous valuable insights into Mao's thinking on literature".

Image copyright Sotheby's

Mao Zedong led the Chinese Communist Party, which defeated the Kuomintang in 1949 and founded the People's Republic of China.

As a young man he worked in Peking University Library and was known throughout his life as a keen reader and writer of classical literature, despite his revolutionary political values.

Sotheby's said the notes had been bought by a Chinese collector, after attracting interest from around the world.

Gabriel Heaton, a books and manuscripts specialist from the auction house, said they gave "an indication of Mao's cultural hinterland, of his interests far beyond politics and his deep knowledge of classical Chinese literature".

Asked why they had gone for a much higher price than the £60,000-80,000 estimate, he said manuscripts written by Mao were "exceptionally rare on the market, which makes it very difficult for us to estimate them in the first place".

Interest in items linked to Mao was strong, particularly in Asia and China, he said.

Earlier this year, a silkscreen portrait of him by Andy Warhol fetched $11m at auction in Hong Kong.