More than 3,700 kg (8,100 pounds) of explosives will be used to demolish the buildings, known as Apex and Ceyane, which are located on the edge of a busy highway that links India's most populous state of Uttar Pradesh to the capital.
The towers were covered with white plastic sheets as police gathered around the area and sealed off arterial roads in preparation for the operation, local television images showed.
People living in the vicinity will have to be evacuated by early Sunday and will be allowed to return to their homes five hours after the demolition has been completed.
Despite rampant illegal building in India's cities, demolitions of large buildings are rare, and locals living close to the site said they feared damage to their properties from the force of the explosions or air pollution from the dust.
