BSP supremo Mayawati and Samajwadi Party chief Akhilesh Yadav met here on Monday after exit polls indicated gains for their alliance in the politically important state of Uttar Pradesh.
Yadav, who had formed a coalition with the BSP and the RLD to take on the BJP, drove to the residence of Mayawati and the closed door talks lasted for almost an hour.
Details of what transpired between the two top leaders was not known immediately.
On Saturday, TDP president Chandrababu Naidu had met both Yadav and Mayawati in the UP capital separately to discuss possibility of non-BJP parties coming together in the event of a fractured verdict.
As part of the alliance agreement, the BSP had contested 38 seats and the SP 37 seats leaving 3 for a smaller RLD while deciding not to field any candidate in Rae Bareli and Amethi, the stronghold of UPA chairperson Sonia Gandhi and Congress president Rahul Gandhi respectively.
The meeting between the SP and BSP bosses on Monday came a day after exit polls projected 300 plus seats for the NDA in the 17th Lok Sabha.
The exit polls showed the mahagatbandhan wresting several seats from the BJP in Uttar Pradesh where the saffron party had won 71 of the 80 seats.
Some exit polls predicted that the SP-BSP alliance is likely to trump the BJP in Uttar Pradesh.
The C Voter-Republic forecast gave the grand alliance in UP 40 seats against 38 for the NDA, while the Jan Ki Baat said the NDA may win 46-57 seats against 15-29 of the SP-BSP combine.
ABP News predicted a huge loss for the BJP in the state, saying it may get only 22 seats while the opposition alliance may emerge victorious in 56 constituencies.
Uttar Pradesh is a politically crucial state as it has 80 Lok Sabha seats.