"We are going to submit a letter to the Governor asking him to suspend the proceedings of the House, and that the House should follow the Constitution," said Devendra Fadnavis after Opposition staged a walkout in protest.
"This session is unconstitutional and illegal. Appointment of pro-tem Speaker was also unconstitutional," he said.
Earlier, as soon as the session begun, Fadnavis said that the special session was also in violation of the rules as it began without the ceremonial singing of 'Vande Mataram'.
"Assembly starts with Vande Matram and ends with National anthem when it is called. This session started without Vande Mataram that is the reason its violating the rules," he said.
Ahead of a floor test for Uddhav-led government, BJP protested in the state assembly against the selection of NCP's Dilip Walse Patil as temporary speaker.
"Never in the history of India has ever pro tem Speaker was changed. Why was pro tem Speaker was changed? Never in the history of Maharashtra Assembly, trust vote was conducted without electing the Speaker. What was the fear this time?" Mr Fadnavis said, moments before the BJP staged a walkout.
Fadnavis also said that they were informed late about the session.
"We were intimated last late night. Why was this done? Was it done because our MLA should not reach the assembly?" he asked.
Responding to Fadnavis, Pro tem Speaker Dilip Walse Patil said that it was with the permission of Governor and hence not against the rule.
"Governor has given the permission for this session last night, this session is as per rule and legal", he said.
Meanwhile, putting an end to weeks of tussle over government formation, Chief Minister Uddhav Thackeray-led Maha Vikas Aghadi Government on Saturday decisively won the vote of confidence securing 169 votes in the 288-member Maharashtra assembly.