Uttar Pradesh Chief Minister Mayawati on Saturday met Prime Minister Manmohan Singh to discuss matters related to the state as also the much-debated issue of the presidential poll.

Congress president Sonia Gandhi joined Dr Singh and Mayawati at a luncheon meeting 30 minutes later when the issue of possible candidates for the presidential poll is understood to have been discussed.

Earlier Mayawati, accompanied by senior state government officials and her trusted lieutenant and minister Satish Chandra Mishra, discussed matters related to the state with the prime minister.

Mayawati's party holds the key in the presidential poll given the fact that the candidate of the ruling alliance can succeed only with the full backing of the Left and the BSP.

Sonia had on Friday hosted a tea party for Mayawati, who took over as Uttar Pradesh chief minister for the fourth time on May 12, but both sides were silent on what transpired at the nearly 100-minute meeting held against the backdrop of hectic efforts by UPA leadership to bring BSP on board on the issue of a successor to A P J Abdul Kalam.