Sources said Singh called BJP President Nitin Gadkari, BJP Parliamentary Party Chief L K Advani, Leader of the Opposition in Lok Sabha Sushma Swaraj and her counterpart in Rajya Sabha Arun Jaitley for support for Ansari who was today declared as the UPA nominee for the post.
Earlier, the PM had sought the support of BJP for Pranab Mukherjee in the Presidential poll but the opposition party refused and backed P A Sangma.
Sources said the party is not likely to support Ansari's candidature in the elections.
The name of the 75-year-old Ansari was announced by UPA Chairperson Sonia Gandhi at a meeting of the Congress-led UPA at Prime Minister Manmohan Singh's residence here.