In a letter to Singh, Rajendra Agarwal claimed that as an advocate Chidambaram had been associated with certain telecom companies in the past and his appointment would amount to "conflict of interest" as he cannot have impartial opinion.
"In the interest of clean and transparent administration in the country, it is necessary to keep Chidambaram out of EGoM," he said.
The BJP has already opposed Chidambaram's appointment as head of the panel.
