JDU leader Nitish Kumar is in Delhi to expedite his return as Bihar Chief Minister.
The BJP will watch the political tussle in the Janata Dal United in Bihar from the sidelines, the party's top leadership has decided, say sources.
They said with state elections due in a few months, the party assesses that any meddling in the current crisis could give Nitish Kumar the chance to be projected as the victim of a political conspiracy.
The JDU has already accused the BJP of conspiring with current Chief Minister Jitan Ram Manjhi, who has refused to resign and make way for Mr Kumar to take over the top post.
At a meeting in the capital, hours after the BJP was dealt a numbing blow in the Delhi assembly elections on Tuesday, top leaders shaped the party's Bihar plans and decided against getting directly involved by supporting
Mr Manjhi if he is asked to prove majority in the state assembly.
The BJP, said sources, would prefer Mr Manjhi breaking away from the JDU with a chunk of leaders and contesting the elections against Mr Kumar.
Nitish Kumar paraded 128 lawmakers before President Pranab Mukherjee today to prove that he has the numbers to be Chief Minister of Bihar. Mr Kumar says he wants a trust vote immediately, but Governor KN Tripathi is delaying it.
Mr Manjhi claims he has the support to remain chief minister. He was picked for the post nine months ago by Nitish Kumar, who quit after his party's rout in the national elections at the hands of the BJP.
The BJP and JDU had contested the last assembly elections together; Nitish Kumar engineered a bitter break-up in 2013.
Last May, the BJP and its allies won 32 of Bihar's 40 seats in the national elections. The JDU got two.
Its performance in the national elections and its recent successes in state elections had buoyed the BJP's assessment of its chances of a big win in Bihar this year.
Rivals, however, allege that its huge loss in Delhi - the BJP won only three of 70 seats yesterday - is proof that its winning streak has now ended.