The deal was struck after AJSU Chief Sudesh Mahto met BJP President Amit Shah and both sides sealed the tie-up.
"BJP has decided to tie up with like-minded parties in Jharkhand and will contest the upcoming assembly polls with AJSU. Talks between AJSU and the state leadership were on and they have been successfully concluded," BJP general secretary Bhupinder Yadav said.
The BJP in its list of candidates, declared on Sunday, had not announced names for five seats, which AJSU had won in the last elections, though it had declared its candidate for Hatia assembly seat, the 6th AJSU seat. AJSU has six MLAs in the outgoing assembly.
Among the assembly seats that BJP has given its new ally are Jugsalai, Chandankyari, Silli, Ramgarh and Lohardaga, currently represented by AJSU, along with the Barkagaon seat.
Yadav said two other seats will be decided by AJSU and its state leadership.
"Our aim is to form a government in Jharkhand with a two-thirds majority that could provide a stable regime to help improve law and order and take the state forward on a speedy path of progress," he said.
AJSU has earlier been part of BJP-led coalition governments in the state but this is the first time both parties will have a pre-poll alliance. Yadav said BJP leaders Raghuvar Das and Arjun Munda had been in talks with AJSU leaders Sudesh Mahto and Chandra Prakash Chaudhary for a pre-poll understanding.
Not ruling out further understanding with some smaller players in the state, Yadav said talks with some such players were on and a tie-up may be finalised for a few seats. He, however, ruled out an understanding with Babulal Marandi's Jharkhand Vikas Party.
The BJP had secured a 44 per cent vote share in the Lok Sabha polls, up from around 28 per cent in the last assembly polls in 2009. AJSU, on the other hand, secured six to seven per cent vote share in the 2009 state polls.
Assembly polls in Jharkhand will be held in five phases between November 25 and December 20 and counting of votes is scheduled for December 23.
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