Incumbent Hamid Ansari is the UPA's candidate for the Vice President's post and is all set to get a second consecutive term.
The name of the 75-year-old Ansari was announced by UPA Chairperson Sonia Gandhi at a meeting of the Congress-led coalition at Prime Minister Manmohan Singh's residence in New Delhi.
A career diplomat, Ansari was the only choice of the UPA which was approved at the meeting, also attended by Trinamool Congress representative and Railway Minister Mukul Roy.
Manmohan Singh also spoke to BJP leader LK Advani before UPA meeting to seek NDA's support.
According to TV reports, PM Manmohan Singh called BJP leader Sushma Swaraj to support Ansari's candidature but she refused to give any committment.
"PM ringed up Mamata Banerjee seeking support of Trinamool Congress for Hamid Ansari," said Trinamool Congress MP Kunal Ghosh.
Trinamool Congress on Saturday said it would soon take a decision on Hamid Ansari as the UPA's Vice Presidential nominee.
Roy, whose party had opposed Pranab Mukherjee's candidature for President's post last month, is believed to have suggested the name of former West Bengal Governor Gopalkrishna Gandhi and former MP Krishna Bose.
However, he applauded the candidature of Ansari once Gandhi announced it.
The Prime Minister also spoke to JD(U) leader Sharad Yadav but got no commitment on support to Ansari's candidature.
Another UPA constituent VCK of Tamil Nadu suggested a Christian candidate.
Neither the UPA Chairperson nor the Prime Minister reacted to these suggestions.
"Mohd Hamid Ansari will complete shortly a term as Vice President of India. He has presided over the Rajya Sabha with dignity and distinction.
"The UPA is honoured to nominate him as its candidate for a second term as Vice President of India," Gandhi said in her brief statement.
The Prime Minister proposed Ansari's name and sought the suggestions of the leaders present. Later Gandhi made the announcement.
As of now, Ansari enjoys a clear edge in August 7 poll.
In an electoral college of 790 MPs, he has the likely backing of over 500 MPs. In the last election, he had polled 455 votes against 222 of Najma Heptullah fielded by NDA.
Rashid Masood of the now defunct United National Progressive Alliance (UNPA) had got 75 votes.
At that time, Ansari's candidature was floated by the Left parties, which were key outside supporters of the UPA.
Home Minister P Chidambaram later said "all leaders" present at the UPA meeting "accepted" the candidature of Ansari.
Asked whether Mukul Roy supported Ansari's candidature, Chidambaram said he "applauded" the announcement.
Roy, however, had a different line as he made it clear that he had not supported Ansari's candidature.
"As the agenda of this meeting was not known to us, we proposed two names -- that of Gopal Krishna Gandhi and Krishna Bose -- as candidates for the Vice Presidential election. But as Ansari's name was proposed by the Congress, we said we will take a decision after consulting with our leadership," he told reporters.
"I will convey today's decision to our party leadership and we will let you know our decision soon," he said.
The Prime Minister and Gandhi spoke to Ansari and offered him congratulations, Chidambaram said.
The Vice President accepted his nomination.
The Prime Minister also spoke to Samajwadi Party leader Mulayam Singh Yadav and BSP chief Mayawati and both welcomed the UPA decision, Chidambaram said.
Singh also spoke to CPI(M) leader Prakash Karat.
Chidambaram said Singh also talked to BJP leader LK Advani before the meeting to indicate that there was "overwhelming" support for Ansari's candidature.