The much-anticipated legal battle between the Birlas and their auditor Rajendra S Lodha over the control of M P Birla group could not begin on Monday as a Calcutta high court judge declined to hear the matter on personal grounds.

Justice S K Mukherjee, in whose court the matter was assigned, told a battery of lawyers representing the two sides, "I am not inclined to take up the matter on personal grounds."

• Birla vs Lodha: War over a will

The matter, which came up for hearing in the second half in a packed courtroom, would now be referred back to the Acting Chief Justice Ajay Nath Roy for re-assignment.

Justice Mukherjee said that his family had a long association with the Birlas and hence it would not be proper for him to hear the matter.

Despite the lawyers representing both the sides saying that they have no objection if the matter was heard by him, the judge stood by his stand and said he was referring the matter back to the Acting Chief Justice.

Both the sides had come well-prepared for the first direct confrontation in the controversy since it broke on July 12 with seasoned lawyer and former Union minister Satyabrata Mukherjee and Samaraditya Pal heading Birla's legal team and Anindya Mitra and Pratap Chatterjee heading Lodha's side.

The case pertains to the petition filed by Lodha challenging the caveats by four prominent Birla family members in the matter relating to the purported will of Priyamvada Birla by which Lodha was bequeathed the entire assets of M P Birla group worth over Rs 5,000 crore.