Mamata Banerjee's sudden flight to Delhi last night has made it clear that she is a key factor in determining the presidential candidate. Congress had wanted that Mamata should support Pranab Mukherjee, but for some reason or the other Mamata is not convinced to support the Union finance minister.  

Mamata had said that she is in favour of candidates like former Bengal Governor Gopal Krishna Gandhi or Lok Sabha speaker Meira Kumar.

On Sunday Manas Bhuniya, who is irrigation minister in Mamata's cabinet and a senior Congress leader in Bengal had appealed to her to support ''Pranabda", as he hails from Bengal. But top Congress leaders are still not convinced that Mamata will support Pranab Mukherjee and for that as a last effort Sonia Gandhi wants to have one to one with Mamata.

The meeting is scheduled to be held this afternoon and a second round of talks might be held on Thursday.The Congress has also fielded former Lok Sabha speaker Somnath Chatterjee for the post.