The INDIA bloc's first meeting was held in Patna in June and the second in Bengaluru last month.
Opposition bloc INDIA is likely to hold its next meeting on August 31 and September 1 in Mumbai, sources said on Friday.
They said it would be held in the format of the Bengaluru meeting with leaders first confabulating in an informal setting on August 31 before their main meeting the next day.
"The opposition meeting will be a two-day affair and will take place on August 31 and September 1 with all leaders approving the dates," a source said.
The likely venue would be a hotel in Powai and there will be a press conference on September 1 evening, the source said.
There have been several dates that have been talked about earlier but those did not work out as all leaders were not available on those dates.
The third meeting of the bloc is being hosted jointly by the Shiv Sena (UBT) and the NCP's Sharad Pawar faction, with support from the Congress -- the three constituents of the Maha Vikas Aghadi alliance. The MVA constituents had been holding parleys to schedule the meeting.
Significantly, Congress leader Rahul Gandhi also met RJD supremo Lalu Prasad Yadav here and discussed a host of issues, including the way forward for opposition bloc INDIA, sources said.
The INDIA bloc's first meeting was held in Patna in June and the second in Bengaluru last month.
The alliance is also likely to announce the composition of committees for specific actions such as communication and 2024 general election campaign in the run-up to the polls.
A joint secretariat for better coordination among the parties is also to be announced soon, the sources said.
During the meeting, the parties are expected to iron out their differences as much as possible, especially in states where they are in a direct poll battle.
At the Bengaluru meeting, Congress president Mallikarjun Kharge had announced the name of the opposition bloc -- Indian National Developmental Inclusive Alliance (INDIA) -- after a nearly four-hour-long meeting of the 26 parties.
He had said a committee of 11 members will also be set up for coordination, and a convenor will be selected at the next meeting in Mumbai.
The 26 opposition parties which are part of the opposition alliance are: the Congress, TMC, DMK, AAP, JD(U), RJD, JMM, NCP (Sharad Pawar), Shiv Sena (UBT), SP, NC, PDP, CPI(M), CPI, RLD, MDMK, Kongunadu Makkal Desia Katchi (KMDK), VCK, RSP, CPI-ML (Liberation), Forward Bloc, IUML, Kerala Congress (Joseph), Kerala Congress (Mani), Apna Dal (Kamerawadi), and the Manithaneya Makkal Katchi (MMK).
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