The Joint Parliamentary Committee (JPC) to be set up to investigate alleged irregularities in 2G spectrum allocation is likely to have 30 members, with senior Congress leader P C Chacko as its head, informed sources said.
According to the sources, the government has agreed to the opposition demand for a 30-member panel for a wider representation of political parties.
The government was earlier planning to have a 21-member panel.
The decision to have 30 members was taken after senior Bharatiya Janata Party (BJP) leaders conveyed to the government that smaller parties also want representation in the panel, the formation of which was promised by Prime Minister Manmohan Singh on Tuesday.
The committee will have 20 members from the Lok Sabha and 10 from the Rajya Sabha and representation of each party would be decided on the basis of its strength in the two houses.
In the 30-member panel, the Congress will have 11 members - eight from the Lok Sabha and three from the Rajya Sabha.
The BJP will have six members - four from the Lok Sabha and two from the Rajya Sabha.
However, BJP sources said that of its four members from the lower house, one will be from its ally Shiv Sena.
Congress ally DMK, whose jailed leader and former communication minister A. Raja is at the centre of the controversy, will have two members and the AIADMK one.
The Nationalist Congress Party (NCP) and the Trinamool Congress - both allies of the Congress - will have one member each. The Bahujan Samaj Party, the Janata Dal-United and the Left will have two each.
The Samajwadi Party and the Biju Janata Dal will also have one member each.
The sources said the Congress has "more or less" made up its mind to have Chacko, an MP from Kerala, as the head of the "sensitive" panel.
Chacko, a Congress old-timer, is considered loyal and reliable to handle the job, they said.
"The government has drafted the terms of reference of the committee and these would be finalized by this (Wednesday) evening," a minister said.
The motion for the formation of JPC will be listed as a supplementary in Thursday's list of business and would be moved by any minister, not necessarily by Telecom Minister Kapil Sibal, at 2 pm in the Lok Sabha.
This will be followed by a discussion and the motion would then go to the Rajya Sabha.