A defiant Mr Nirupam had said he would announce his next course of action on Thursday.
Capping a day of fast-moving developments, the Congress has expelled Sanjay Nirupam, a senior leader from Maharashtra, for six years for his "anti-party statements". Earlier on Wednesday, the party had removed him from the list of star campaigners for the Lok Sabha elections and sources had said that a proposal to expel him was being prepared by the state unit to be sent to the central leadership.
The proposal was made after Mr Nirupam made a string of remarks against Congress' INDIA ally, Shiv Sena (Uddhav Balasaheb Thackeray) and its leader Uddhav Thackeray after it announced some candidates for the Lok Sabha constituencies in Maharashtra - including the North West Mumbai seat, which was reportedly being eyed by the Congress leader.
Before that, he had also made remarks on the arrest of Delhi Chief Minister Arvind Kejriwal, the convenor of another party ally, AAP, which were not in line with the Congress' official stand.
Announcing Mr Nirupam's expulsion late on Wednesday, Congress General Secretary KC Venugopal said in a statement, "Taking note of the complaints of indiscipline and anti-party statements, the Hon'ble Congress President has approved the expulsion of Shri Sanjay Nirupam from the party for six years with immediate effect."
Earlier in the day, Maharashtra Congress President Nana Patole had said, "We have taken him (Mr Nirupam) off the list of star campaigners and have also initiated disciplinary action against him over the statements he made."
After he was removed as the star campaigner, a defiant Mr Nirupam had hit out at the Congress and said he would announce his next course of action on Thursday.
Personal Attacks
The Shiv Sena (UBT), which is in the Maha Vikas Aghadi alliance in Maharashtra with the Congress and the NCP, had declared its list of 16 candidates for the Lok Sabha elections on March 27. The list included the name of Amol Kirtikar - son of the sitting MP - for the North West Mumbai seat, prompting a tirade from Mr Nirupam.
"The way Shiv Sena UBT has taken five seats of Mumbai, it seems that there is a plan to bury Congress in Mumbai. It seems the Shiv Sena wants to force Congress to kneel," the senior Congress leader, who has been a Lok Sabha MP from the Mumbai North constituency, a Rajya Sabha MP and the Mumbai unit president of the party, said.
"I appeal to the Congress leadership to intervene or end the alliance with Shiv Sena. If the Shiv Sena thinks it can fight alone, it is making a big mistake," he added.
Taking a dig at Uddhav Thackeray over the split in the Shiv Sena engineered by the current Maharashtra Chief Minister Eknath Shinde, Mr Nirupam called him the "bachi kuchi Shiv Sena pramukh (chief of what's left of the Shiv Sena)".
He also hit out at Mr Kirtikar, alleging that he was involved in the 'Khichdi scam' - the alleged irregularities in the distribution of food to migrant workers during the Covid-19 pandemic.
Mr Nirupam's remarks were seen as adding to the seat-sharing troubles of the Maha Vikas Aghadi, which is part of the INDIA alliance at the Centre.
'Will Announce Decision Tomorrow'
After he was removed from the list of star campaigners, Mr Nirupam had alluded to the Congress' accounts being frozen and said it should utilise its stationery and energy to save itself.
In a post on X, the leader wrote in Hindi, "The Congress party should not waste energy and stationery on me. It should utilise the stationery and energy to save itself since the party is experiencing a serious financial crisis. The timeframe I had given to the party ends today. I will spell out my next course of action tomorrow," he tweeted.
The timeframe was a reference to his earlier comments giving the Congress a week to decide on ending the alliance with the Shiv Sena (UBT).
Should Mr Nirupam decide to switch sides, he is likely to be spoilt for choice as leaders from both the BJP and the Eknath Shinde faction of the Shiv Sena have said he would be welcome in their parties.