Here are the latest developments
"If in the next 2-3 days, we don't get an answer from the BJP, then we will sit in Opposition," Mr Thackeray warned.
He said in that case, Sena leader Eknath Shinde will be Leader of Opposition in the Maharashtra Assembly, which convenes on Monday.
Mr Thackeray refused to say whether the Sena was also contemplating pulling its one minister Anant Geete out of the Narendra Modi government at the Centre. "I will decide at the right time," he said.
The BJP and Shiv Sena, who have been trying to recalibrate their alliance, seemed to have been driven to break-point for most part of Sunday by PM Modi's cabinet expansion in Delhi.
For one, the PM inducted Suresh Prabhu into his cabinet at the Centre. Mr Prabhu, who was a member of the Shiv Sena, joined the BJP on Sunday morning in a major snub to the Sena.
The Shiv Sena had nominated Anil Desai for its "quota" of a Cabinet minister. Mr Desai flew to Delhi on Sunday morning. But after the BJP made it clear that Mr Desai would rank as a junior minister, Mr Thackeray ordered him to fly back to Mumbai. "We chose not have Anil Desai inducted at the Centre due to the uncertainty at the state level," said Mr Thackeray.
The BJP and Shiv Sena called off a 25-year alliance in Maharashtra ahead of the state elections. The Sena ran a maximally vicious campaign. The BJP won the most seats but not a majority. The Sena is the number 2 party.
Chief Minister Devendra Fadnavis will take a trust vote on Wednesday. The Sena wanted to be added to his government before then, which the BJP has refused to allow.
The BJP wants the Sena to accept that its junior partner status cannot entitle it to the post of Deputy Chief Minister or an important portfolio like Home or Finance. Mr Thackeray had reportedly conveyed that without those offices, the Sena would prefer to serve as the Opposition in Maharashtra.
Sharad Pawar has said his NCP will support the BJP's minority government but he has a poor record as an ally which is why the BJP has been keen to strike a deal with the Sena.
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