AIADMK (Amma) led by Palanisamy accused the O Panneerselvam faction of "refusing" to come for talks.
On the other hand, the AIADMK Puratchi Thalaivi Amma faction maintained that discussions "will happen" only after its demands, including a CBI probe into former chief minister J Jayalalithaa's death, were met.
Apparently peeved at the 'delay' in commencement of talks, state Finance Minister D Jayakumar told reporters that the time was "ripe for talks."
"But they (Panneerselvam camp) are refusing to come to the table," he said, adding that the discussions will be "transparent".
Sticking to their stand for commencement of merger talks, Panneerselvam aide and Rajya Sabha member V Maithreyan reiterated the Puratchi Thalaivi Amma faction's demand for the state government recommending a CBI probe into Jayalalithaa's death, besides removal of party chief V K Sasikala and members of her family from the party.
"Only if these demands are met, the talks will happen. We are clear on that," he said.
The two groups have been expressing their willingness to sit across the table and discuss the proposed merger since they set up their respective seven-member committees for the purpose last week. However, the talks have not commenced so far.
The Palaniswami camp had revolted against the party leadership on April 18 and resolved to keep Sasikala and her family, including her nephew and deputy T T V Dinakaran, away from the AIADMK.
Dinakaran, AIADMK (Amma) Deputy General Secretary, was later arrested for allegedly attempting to bribe an unidentified Election Commission official to secure the 'Two Leaves' symbol of the undivided party (prior to the R K Nagar assembly byelection.)
The April 12 by-election was subsequently countermanded over use of money to lure voters.
Hopes of an early start of talks had received a boost on Wednesday when the banners of Sasikala at the AIADMK office here were pulled down, a move welcomed by the Panneerselvam group.