Shiv Sena (UBT) MLC Sachin Ahir on Tuesday filed his nomination for the Maharashtra Legislative Council deputy chairman's post as the Mahayuti candidate, signalling his switch to the Eknath Shinde-led Shiv Sena.
The election for the post will be held on Wednesday.
Ahir, considered a close aide of Shiv Sena (UBT) leader Aaditya Thackeray, filed his nomination in the presence of Chief Minister Devendra Fadnavis and Deputy Chief Ministers Eknath Shinde and Sunetra Pawar.
His move comes days after six Shiv Sena (UBT) Lok Sabha MPs joined the Shinde-led Shiv Sena under what party leaders described as "Operation Tiger."
A former minister, Ahir played a key role in strengthening the Shiv Sena (UBT)'s organisation in Worli and was instrumental in consolidating support for Aaditya Thackeray during the Assembly elections.
Ahir was previously with the Nationalist Congress Party before joining the undivided Shiv Sena in 2019. He was nominated to the Legislative Council in 2022.
Reacting to the development, Maharashtra BJP president Chandrashekhar Bawankule said the BJP had no role in Ahir's decision but blamed repeated defections on the "arrogance" of Uddhav Thackeray and Shiv Sena (UBT) MP Sanjay Raut.
Bawankule said the party leadership had failed to treat its workers properly and that the exits reflected growing dissatisfaction within the organisation.
Meanwhile, Shiv Sena (UBT) leader and Leader of the Opposition in the Legislative Council Ambadas Danve said MLC Jagannath Abhyankar was the Maha Vikas Aghadi's candidate for the deputy chairman's election.