Patna, Dec 25 (IANS) Six parties of the Janata Parivar will merge in January to take on the BJP, leaders of the JD-U and its ally RJD said here Thursday.

"After the result in the Jharkhand polls, six parties will merge in January to stop the winning rath (chariot) of the BJP ahead of the Bihar assembly polls next year," Janata Dal-United state president Vashisht Narayan Singh said.

He said a new party will be formed in Bihar and at the national level.

His views were strongly supported by Rashtriya Janata Dal (RJD) leader Abdul Bari Siddiqui, a close confidant of party chief Lalu Prasad.

"It is the need of the hour for a merger soon to counter the BJP in Bihar ahead of the assembly polls," said Siddiqui, the leader of the RJD in the assembly.

Siddiqui said the six parties will launch a joint campaign after the merger.

Samajwadi Party chief Mulayam Singh Yadav has been authorised to work out the modalities for the merger.

Last month, the JD-U and the RJD said they will merge ahead of the polls in 2015.

Lalu Prasad and JD-U leader Nitish Kumar had jointly campaigned for the by-election in Bihar in August. That was the first time the two leaders came together after 20 years.

Lalu Prasad said he and Nitish Kumar wanted to send a strong message across the country to unite non-Bharatiya Janata Party (BJP) forces.

The JD-U had ended a 17-year alliance with the BJP last year after Narendra Modi was named as the prime ministerial candidate.