The announcement was made after a special meeting of the Union Cabinet, which condoled the death of the anti-apartheid icon.
During the period of state mourning, the national flag will be flown at half mast from December 6 to 10 throughout the country, and there will be no official entertainment.
Mandela, who guided South Africa from the shackles of apartheid to multi-racial democracy and became an international icon of peace and reconciliation, died at his home on Thursday at age 95.
Mandela had spent nearly three months in a Pretoria hospital with a recurring lung infection, and was shifted to his home in September with all intensive care facilities made available to him.
Mandela had spent 27 years as a prisoner in South Africa for opposing apartheid, and then emerged to become his country's first black president.
He was bestowed with the Nobel Peace Prize and he became an enduring symbol of integrity, principle and resilience.
--ANI (Posted on 06-12-2013)