The British-born 80-year-old author of '2001: A Space Odyssey', who lives in Sri Lanka, requested the postponement following allegations about his private life in the British newspaper the Sunday Mirror.
In a statement, Mr Clarke said he was outraged by unsubstantiated newspaper allegations that he had a history of sexual relations with young boys. He had asked for the delay to avoid embarrassment to Prince Charles.
Mr Clarke, who is credited with predicting the future of satellite communications, was named by the Queen in the New Year's Honours List.
A BBC correspondent in Colombo says the newspaper article has led to calls in Sri Lanka for an investigation into the allegations and even some demands for Mr Clarke to be deported.
Prince Charles was due to knight Sir Arthur at a ceremony in the Sri Lankan capital of Colombo on Wednesday while on a four-day visit marking the island's 50th anniversary of independence from Britain.
Protests precede Charles's visit to Sri Lanka
(02 Feb 98 | World)
The new knight of science fiction
(31 Dec 97 | UK)
The Arthur C. Clarke Foundation
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