New Delhi, Apr 14 (IANS): The Prime Minister's Office Sunday dismissed as "baseless and mischievous" claims by Prime Minister Manmohan Singh's former media adviser Sanjaya Baru that its files were seen by Congress president Sonia Gandhi.

"The statement being attributed to a former media adviser to the prime minister that PMO files were seen by Congress president Sonia Gandhi is completely baseless and mischievous. It is categorically denied that any PMO file has ever been shown to Sonia Gandhi," Pankaj Pachauri, communications adviser to the prime minister, said in a statement here.

"The commentary smacks of fiction and coloured views of a former adviser," the statement said.

"The book written by the former media adviser is an attempt to misuse a privileged position and access to high office to gain credibility and apparently exploit it for commercial gain," it sa.

Baru has claimed in his book "Accidental Prime Minister: The Making and Unmaking of Manmohan Singh" that a senior official in the PMO would seek "instructions" from Gandhi on important decisions.

The PMO statement said: "The question about comments of the former media adviser was raised by senior editors when they met the prime minister in October last year. His answer was - 'Do not believe all he is saying'."

In the book that has sent ripples across the political establishment for its timing and content, Baru has said that Gandhi slowly chipped away at the authority of the Prime Minister's Office, created a parallel power structure and left a weakened prime minister who "allowed himself to become an object of such ridicule in his second term in office".

Baru had resigned from the PMO in 2008.