According to officials, Mr Mehrishi's appointment was recently cleared by the government. A 1978-batch (retired) Indian Administrative Service (IAS) officer of Rajasthan cadre, he completed his two-year fixed term as the home secretary last month.
Mr Sharma had taken over as the CAG on May 23, 2013. He was the defence secretary prior to his appointment as the CAG. He will have a tenure of about three years. The CAG is appointed for a term of six years or till the incumbent attains the age of 65 years, whichever is earlier.
As a constitutional functionary, the CAG is primarily entrusted with the responsibility of auditing the accounts of the Union government and the state governments. The CAG reports are laid before Parliament and legislatures of the states.
Before his appointment as the home secretary, he worked as economic affairs secretary and chief secretary of Rajasthan. He has also worked as secretary in departments of chemicals and fertilisers, and Overseas Indian Affairs.