It will be the third such exercise since he took over in May 2014.
"A process has been set in motion for the swearing-in ceremony at Rashtrapati Bhavan around 10 am on Sunday," the official said.
Four junior ministers - Rajiv Pratap Rudy, Sanjiv Kumar Balyan, Faggan Singh Kulaste and Mahendra Nath Pandey - have resigned ahead of the rejig.
Two cabinet ministers have also offered to resign, said BJP sources.