Feb. 5: Saradha has drained Trinamul out of Srinjoy Bose's teacup, prompting a scramble to read the tea leaves left behind.

Bose today resigned from Trinamul and announced his decision to quit as Rajya Sabha MP, saying that "during my days in custody, I had finally realised that politics is not my cup of tea".

Srinjoy, known as Tumpai and part of the quintet about whom Mamata Banerjee asked whether they were thieves ("Tumpai chor?"), was in custody (mostly in hospital) in connection with a Saradha case for 75 days and was freed on bail last night.

Sources have been saying that the Bose family had decided sometime ago that it was best for Srinjoy to leave politics. But the timing of his announcement - so soon after being released from custody - ignited speculation on "other factors" that might have persuaded him to snap his ties with Trinamul.

The Bose family's association with Trinamul goes some way back. Srinjoy's father Swapan Sadhan Bose (Tutu) used to be Trinamul Rajya Sabha MP before the baton was passed on to the son.

The first to stir the speculation pot was Trinamul Rajya Sabha chief whip Derek O'Brien. Although O'Brien termed Bose's decision a "personal choice", "his prerogative" and "democratic right", he did not miss the opportunity to suggest a motive.

"We have been saying for some time now that he has been put under tremendous pressure by the party in power at the Centre. He was released on bail yesterday. He resigned today. Did this pressure lead to some co-ordination?" asked O'Brien in a statement posted on the Trinamul website.

BJP state president Rahul Sinha shovelled some fuel into the fire. "Srinjoy was not supposed to be in jail.... The family that he comes from, they have enough money and I personally think he had no need to be involved in financial irregularities. It was the company that he had in the party that brought him down," said Sinha, blaming Trinamul for Srinjoy's legal troubles.

The charitable words led to the question - inevitable in Bengal where most Trinamul leaders are playing a guessing game of "who will jump the ship" - whether the BJP is beeping on Srinjoy's radar.

"There is no point of him joining the party," said Sidharth Nath Singh, the BJP's minder for Bengal.

CBI sources who had said yesterday that an appeal would be filed against Srinjoy's bail were less categorical today. But they said the final decision would depend on legal advice, especially in the light of a Supreme Court statement earlier that bail should be the norm and jail the exception until a person is found guilty.

Sources close to Srinjoy contested suggestions of a deal with the BJP. A release circulated by Srinjoy's office said he took the decision following family pressure.

"There has also been a lot of pressure from my family, specially from my mother and wife which, finally, made me take this decision," Srinjoy said in the statement.

On his release from SSKM Hospital yesterday, Srinjoy was admitted to Belle Vue Clinic with complaints of acute pain in the lower back. Sources in the hospital said he called his secretary to the hospital this morning to initiate proceedings to formally snap ties with Trinamul and step down from the Rajya Sabha.

"He had taken the decision some time ago and he merely announced it today," said a Trinamul source, adding that the party leadership was not surprised with the move.

In the release issued by Srinjoy's office, the Trinamul MP thanked Mamata. "I am thankful to my Didi, Smt Mamata Banerjee, that she had thought me capable enough to make (me) an MP."

Even as speculation continued on what could have prompted Srinjoy to distance himself from the Trinamul establishment, the announcement brought cheer in the BJP camp on a day actress Locket Chatterjee, one of the known faces in Mamata Banerjee's culture clan, switched over to the BJP.

While it is true that both Bose and Chatterjee hardly had any political role in the ruling establishment, the timing of their departure from Trinamul is an embarrassment for the party and is likely to send a signal to the ranks.

Last week, Mamata said the BJP was trying to break up the party, betraying her worry about possible defections.

"The cookie has crumbled. People are leaving Trinamul.... Wait for more surprises," said Singh, adding that more people would desert Trinamul's "sinking ship".

The Trinamul camp, however, tried to cut a brave face. Abhishek Banerjee, Mamata's nephew and the de facto number two in the party, stressed that he was not bothered.

"Our party chief has said this in the past, that if you have to stay in the party, you have to be willing to fight. Those who do not possess the temperament to fight are free to leave. That's what Srinjoy did," Abhishek said at Trinamul Bhavan this evening.

Trinamul sources said Mamata would soon announce the name to replace Srinjoy in the Rajya Sabha, where Trinamul has 12 members.

If Srinjoy's resignation is accepted by Rajya Sabha chairperson and Vice-President Hamid Ansari, an election will have to be held in the next six months.

Asked about the process to resign from the upper House, former Assembly Speaker Hashim Abdul Halim said: "A Rajya Sabha member cannot resign just by sending his or her resignation.... Instead, he or she has to personally meet the chairperson to tender a hand-written resignation."

In order to tender a hand-written resignation, Srinjoy will have to travel to Delhi. For that, he needs a nod from the Alipore judge's court that granted him conditional bail and barred his movement outside Calcutta.

"But he can seek permission from the court to go to Delhi," said a lawyer.