In retirement, he wrote a biography of Chinese national leader Deng Xiaoping.
Zhao also began to lose favour with paramount leader Deng Xiaoping.
As the Chinese leader Deng Xiaoping himself put it, two systems would coexist within one country.
Yu was friends with former leader Deng Xiaoping and his family.
"All the officials are inside studying the speech of senior leader Deng Xiaoping."
In practice, state and party leaders still deferred to paramount leader Deng Xiaoping.
The former leader Deng Xiaoping introduced market reforms 30 years ago that have helped to turn China into the world's second-largest economy.
Both sides needed the backing of paramount leader Deng Xiaoping to carry out important policy decisions.
Since the situation seemed intractable, the weight of taking decisive action fell on paramount leader Deng Xiaoping.
The program was authorized on 19 April 1983 by then-paramount leader Deng Xiaoping.