Sources said that as of now, a 21-member JPC was being thought of and the parties will make it to the panel on their strength.
AIADMK Parliamentary Leader M Thambidurai made a strong plea in the Lok Sabha that leaders of all political parties should be given representation in the JPC in order to avoid any feeling of neglect.
The NCP, an ally of the UPA, has communicated to the Congress that all major parties in the ruling alliance should be represented in the JPC.
If the JPC has 21 members, 14 would be from the Lok Sabha and seven from the Rajya Sabha.
In such a scenario, only seven to nine of the total 37 parties in Parliament could be accommodated.
While the names of senior Congress leaders PC Chacko and V Kishore Chandra Deo are doing the rounds for the post of Chairman, no decision has been taken on the issue.
The names of BJP deputy leader in the Rajya Sabha SS Ahluwalia and CPI(M) Politburo member Sitaram Yechury were being talked about among the Opposition members on the proposed body.
Congress, BJP, Trinamool Congress, Samajwadi Party, BSP, JD(U) and DMK could get their members on the panel in view of their numbers.
Prime Minister Manmohan Singh today announced in Parliament about his government's decision to set up a JPC into the 2G spectrum scam.