Edited by Mala Das | Updated: July 16, 2012 16:54 IST
The BJP and its allies that make up the NDA coalition met this morning and decided Mr Singh will be their candidate.
Senior BJP leader LK Advani said that the coalition wanted Sharad Yadav, the convenor of the NDA, to run for vice-president, but he declined. Mr Yadav is a senior leader of the Janata Dal (United), which is in power in Bihar with Nitish Kumar as chief minister. The BJP is the junior partner in the state government.
The JD (U) has said it will support Mr Singh. So will another important BJP ally, the Shiv Sena.
For the election for President of India, scheduled for Wednesday, the JD(U) and the Sena are voting for Pranab Mukherjee, who is the UPA's candidate. They felt Mr Mukherjee has more experience than the BJP's candidate for President, PA Sangma.
If the JD(U) had chosen to side with the UPA again on the matter of vice-president, it would have created a new bout of awkwardness for the BJP.
The issue of vice-president also has the potential to expand the chasm between the Congress and its estranged ally, Mamata Banerjee. She was not originally in favour of supporting Mr Ansari, but sources say back-channel talks are progressing well and she may come around. (Watch)
Ms Banerjee has, so far, refused to indicate whether her party's MPs and state legislators will vote for Mr Mukherjee in the presidential election. She is expected to share her decision tonight.
Ms Banerjee fell out with the UPA last month over her opposition to Mr Mukherjee as the coalition's candidate. He has since written to her MPs and to Ms Banerjee, asking for her support.
Mr Singh does not really present stiff competition to Mr Ansari. The UPA, supported by the Samajwadi Party and Mayawati's BSP, have 444 MPs; they need 396 votes to have Mr Ansari elected.
Though the math is against them, the BJP wants to make a point by fielding candidates in the election for vice-president and president. With the general elections in 2014, the BJP does not want to be seen as voting on the same side as the government.
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