A letter sent from Mao Zedong to future British prime minister Clement Attlee in 1937 has sold for £605,000 ($917,319) at Sotheby's London.
It beat an estimate of £150,000 ($227,434) by 303.3% in a sale earlier today.
Mao contacted Attlee to request British help following the Japanese invasion. He writes: "We know that the great majority of the British people stand firmly for peace and democracy…
"The Chinese people, like the people of Spain, stand now in the vanguard of the International Peace Front. Our Party and our Army are playing their part in that struggle.
"We are fighting with the whole Chinese people against an enemy that has deliberately turned against peace and the welfare of humanity."
Mao was encouraged to write to Attlee, then leader of the opposition British Labour party, by journalist James Bertram - who made the dangerous trip through war-torn China to interview him.
Attlee lacked the power to provide any tangible help, but clearly remembered the letter in later years. In 1950 he was among the first heads of state to recognise the People's Republic of China.
He was also one of the first western politicians to travel to the newly formed nation in 1954.
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