Congress MLAs were also part of the delegation of opposition parties that met Rao in Chennai.
The DMK leader demanded an immediate floor test from the Governor.
He demanded an order for Chief Minister Edappadi K. Palaniswami, seeking a vote of confidence and resolves the political crisis in the state.
He apprised the Governor of the current tally of MLAs by his side. According to him, 119 MLAs are with him, as against the 114 with the Chief Minister, which is more than the majority which the assembly demands.
He added that they have met the Governor a number of times and if he does not respond to the request within a week then he will "have to take legal resort and mobilise people's mandate".
He also said that he will approach the people's court as well.