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Congress vice president Rahul Gandhi, Bihar Chief Minister Nitish Kumar, Sitaram Yechury of the Left and Majeed Memon of the Nationalist Congress Party were the opposition leaders who made it.
RJD chief Lalu Yadav had accepted the invitation but had to drop out at the last minute due to "high fever", Nitish Kumar told the thousands of DMK activists at the event.
Karunanidhi, recovering from illness, wasn't there to hear the leaders laud his contribution to the state, and the country. He is recuperating at his Gopalapuram residence where he was visited by Nitish Kumar in the evening .
His son and DMK Working President MK Stalin, who appeared to be positioning himself for a bigger role in Tamil Nadu, hosted lunch for the high-profile guests. Rahul Gandhi joined him for tea.
Nitish Kumar predicted that Mr Stalin would head the next government in Tamil Nadu and asked him to implement his father promise on prohibition.
"All of us on the stage, people in the crowd, and all those watching will not let the RSS or Narendra Modi impose one idea on this country, Rahul Gandhi said, pledging to fight any attempt to do so. "We are not going to stand and watch while they peddle their ridiculous ideas," he said.
Former Chief Minister of Kashmir, Omar Abdullah said "I am here to start a new chapter with Stalin and all these parties across the country. We want to tell the BJP you can't dream of a country without the Congress and Opposition.
Derick O'Brien, Trinamool Congress MP suggested his party boss was prepared to work with other parties in national politics. "Mamata is ready. Regional parties should go to Delhi. We are ready, are you ready? "
The event came amidst parleys by parties not part of the BJP-led National Democratic Alliance to field a common candidate for the Presidential polls due in July. However, both Stalin and his sister Kanimozhi have denied the birthday party will serve as a platform for the opposition parties to discuss the Presidential polls.
"It is a very special day for all of us. Karunanidhi's emphasis on social justice is his greatest contribution as legislator. There is nothing politically significant about opposition leaders meeting," Karunanidhi's daughter Kanimozhi told NDTV.