Uncertainty clouds the grand opposition meeting planned for November 22 even as Andhra Pradesh CM Chandrababu Naidu heads to Kolkata to meet counterpart Mamata Banerjee to cement support for an anti-BJP coalition.

Naidu has been trying to forge an anti-BJP alliance of regional parties, along with the Congress, ahead of the 2019 Lok Sabha elections. In the past few weeks, he has met several regional leaders and Congress chief Rahul Gandhi to discuss the same. Naidu had earlier announced an anti-BJP party conclave in the capital, for which he had met Congress general secretary Ashok Gehlot in Amaravati.

But it hasn't been smooth sailing. With both Samajwadi Party chief Akhilesh Yadav and Bahujan Samaj Party chief Mayawati criticising the Congress in the past week, Mamata Banerjee had raised questions over the timing of the meeting. "The issue is that if all opposition leaders aren't present at the meeting, then it doesn't show a united front and doesn't show solidarity," she said.

Akhilesh had accused the Congress of attempting to scuttle his party's chances in Chhattisgarh, while Mayawati described both the BJP and Congress as "snakes", adding that she would rather remain in opposition than ally with either.

While Banerjee has argued for the presence of both Akhilesh and Mayawati at the rally, concerns were also raised by NCP president Sharad Pawar, sources said. "Sharad Pawar and Mamata Banerjee spoke on Saturday and concerns were raised about the role that the Congress was playing ahead of the meeting. It appeared that the Congress was trying to hijack the situation and take control of the entire matter," said a source.

Concerns were also raised about the role of Ashok Gehlot, whom Naidu had roped in for coordinating the meeting.

Banerjee remains in touch with the Congress leadership, said sources in Trinamool Congress. A senior leader from the party maintained that among the proposals was a meeting in the capital during the Winter Session of Parliament.

However, a senior TDP leader maintained that supporting the Congress through a united front at a time when Assembly elections are underway would aid the opposition ahead of the 2019 Lok Sabha polls. Stitching an alliance of different regional parties with diverse political views isn't easy, said the leader. Take, for instance, the fact that Naidu had suggested that the November 22 meeting in Delhi could take place at Andhra Bhawan while also suggesting the "more neutral venue" of the Constitution Club, said the leader.

Last week, the Andhra Pradesh government also withdrew its general consent given to the CBI, which is being seen as an all-out war between Naidu and the BJP-led Centre. Banerjee followed suit, supporting Naidu.