Banerjee announced after a meeting with Congress president Sonia Gandhi that the ruling party's first choice for president was Finance Minister Mukherjee and the second was Ansari, the current vice president. Barely an hour later, Mulayam Singh Yadav and Mamata Banerjee, in a joint press conference, said their preferred choices were former president A.P.J. Abdul Kalam, Manmohan Singh and former Lok Sabha speaker Somnath Chatterjee.

"We discussed three names ... A.P.J. Abdul Kalam, Manmohan Singh and Somanth Chatterjee," Mulayam Singh told reporters, bringing the prime minister's name in the reckoning for the first time.

"We decided the names based on the persons who are honest, know the constitution and can work for the nation. It will be good to have a president elected unanimously by all political parties," Banerjee said.

Both leaders denied the names were in any order of priority and said it was for the political parties to support one of them.

The fact that Banerjee, who spent the day confabulating with key political leaders, announced one set of names and then another in a space of just a short time set tongues wagging.

With five names in the running where there was only one -- Nationalist Congress Party's (NCP) P.A. Sangma -- the political world was thrown into a whirl.

With two key allies virtually saying that he should leave 7, Race Course Road for Rashtrapati Bhavan, was this the end of Manmohan Singh's prime ministership? Where would it leave Mukherjee, the quintessential second-in-command and the government's most valued troubleshooter?

Most political observers were of the view that Chatterjee and Kalam were red herrings and the Congress may not have been all that serious about Ansari - who did not get the support of the SP, which had said it wanted a political nominee, preferably a Muslim.

The SP and the Trinamool with their decisive numbers are critical to the UPA pushing ahead with its choice for president. The other allies, NCP and DMK, had earlier said they would go with whoever the Congress chooses. But with no one name, it was confusion confounded.

With the government under unprecedented attack, its very leadership being questioned because of a perceived policy paralysis and a floundering economy, how this roulette will play out in the next days will have a bearing on the future of the UPA, its government and the way it prepares itself for the next general election scheduled for 2014.

There were many questions doing the rounds. Was this a well-scripted drama or did the allies pull the rug from under the Congress' feet?

The Congress retreated into a shell and no comments were forthcoming from their spokespersons. The Prime Minister's Office also said "no comment" to journalist questions about the prime minister's future.

"The SP and Trinamool are UPA allies... there is nothing wrong in a political party suggesting names. No decision has been taken. These names can be discussed and a consensus arrived through dialogue," said a senior Congress leader on condition of anonymity.

The opposition NDA said they would wait and watch for the official position to emerge before making known their choices.

Both alliances have till June 30 to file nominations. Elections, if required, would be held July 19.