Ahead of the United Progressive Alliance's meeting on Friday evening, talks between the Congress and Samajwadi Party gained momentum over the possibility of Mulayam Singh Yadav's support to the ruling dispensation candidate for the presidential poll.

Sources in the Samajwadi Party said that Yadav, his cousin and party general secretary Ram Gopal Yadav and another senior leader Naresh Aggarwal have held at least five rounds of discussion with Congress leaders.

While Yadav and TMC chief Mamata Banerjee had floated the names of Prime Minister Manmohan Singh, former Speaker Somnath Chatterjee, former President APJ Abdul Kalam as their presidential candidate, the SP chief on Thursday night refused to declare Kalam as his preferred candidate.

He is understood to have told Banerjee that any final decision on a single name has to be endorsed by other SP leaders.

Meanwhile, Aggarwal and Ram Gopal Yadav met Mulayam Singh Yadav on Friday morning amid indications that the SP chief could leave for Agra today.

The UPA meeting later in the day is expected to formally endorse the name of Pranab Mukherjee as the alliance candidate.