Along with his identical twin Sir Frederick, Sir David built a vast business empire which began with hotels and expanded to include shipping, retailing, and, since 2004, ownership of the Telegraph Media Group.
The paper said the Barclay brothers had “operated as one” throughout their business career, while steadfastly avoiding personal publicity and media scrutiny.
They had turned to media ownership in 1992 by buying the weekly newspaper The European, which closed in 1998, while they had also owned The Scotsman from 1995-2005.
After first expressing interest in The Daily Telegraph to its Canadian owner Conrad Black in May, 2003, and while a private deal was overruled by a US court in November of that year, the Barclays eventually acquired the paper at auction seven months later for £665 million.
It was reported Sir David died on Sunday.