Once-arch rivals Samajwadi Party and Bahujan Samaj Party announced on Saturday their tie-up in Uttar Pradesh for the 2019 Lok Sabha polls, sharing 38 seats each and keeping the Congress out of the alliance.
The parties, however, said they would not field candidates in Amethi and Rae Bareli, represented by Congress president Rahul Gandhi and UPA chairperson Sonia Gandhi.
They also left two seats out of the 80 in the state for smaller allies, without naming them. But there have been talks with Ajit Singh's Rashtriya Lok Dal.
Making the announcement at a joint press conference with SP president Akhilesh Yadav in Lucknow, BSP chief Mayawati said, "This...will rob ‘guru-chela’ -- Prime Minister Narendra Modi and Bharatiya Janata Party president Amit Shah -- of their sleep."
"I have full confidence that just as our alliance defeated the BJP in the Lok Sabha bypolls, we will crush the saffron party in the general elections," she said, referring to the BJP's defeat in Phulpur, Gorakhpur and Kairana parliamentary bypolls.
In Varanasi, senior Congress leader P Chidambaram hoped the Lucknow announcement wasn't the last word and a broad-based alliance would be formed in the state as polls approach. But he also asserted the Congress was ready to fight alone.
Senior Congress leaders including the UP in-charge at All India Congress Committee, Ghulam Nabi Azad, will be in Lucknow Sunday to discuss the party's strategy, a spokesperson said.
Reacting to the alliance announcement, the Bharatiya Janata Party's Ravi Shankar Prasad said the two parties had came together just for their own survival.
In his address at the BJP national convention a little after the UP development, Modi didn't refer directly to the SP-BSP deal but dismissed opposition efforts at coalition-building as a 'failed experiment' to bring in a 'helpless government'.
In 2014, the BJP had won 71 seats in Uttar Pradesh while its ally Apna Dal bagged two. The Samajwadi Party won five seats and the Congress two, while the BSP drew a blank.
At the press conference at a posh Lucknow hotel, Mayawati asserted that the two parties were entering into a long-term understanding.
"This will last long, beyond Lok Sabha polls and in the UP assembly elections," the BSP leader said.
Akhilesh Yadav avoided a direct reply when asked if he would support Mayawati for the prime minister's post if the situation arose.
"You know whom I will support," he said. "I have said in the past that UP has always given the PM (to the country) and I will be happy if it gives a PM again."
To a question on seat-sharing with the Rashtriya Lok Dal in western UP, the SP leader said the media would be informed in due course.
RLD spokesperson Anil Dubey later said as far as his party is concerned, the alliance talks are still on.
Yadav and Mayawati did not make it clear whether they will themselves contest the polls, which are to be held by May.
Mayawati accused the BJP of spending a massive amount of money on Shivpal Yadav, saying his recently floated Pragatisheel Samajwadi Party-Lohia was being 'run by the BJP'.
"The money will go down the drain," she said, even as Shivpal Yadav, the estranged uncle of Akhilesh Yadav, rejected her allegation later in the day.
Mayawati said in the national interest, she had moved passed the 1995 Lucknow guest house incident, in which some SP supporters had attacked her. The last state-level alliance between the two parties had ended around that time.
Yadav asked SP workers to ensure Mayawati gets the respect due to her.
"Mayawati's respect is my respect. An insult to her is an insult to me. If any BJP men or others say anything against her, it will be against me," Yadav said, seeming to warn against a repeat of the 1995 incident.
He asked party workers to be on guard against the BJP, alleging that the party could orchestrate riots and create differences between the two opposition parties.
West Bengal chief minister and Trinamool Congress chief Mamata Banerjee welcomed the SP-BSP alliance.
BJP leader and Union minister Ravi Shankar Prasad said the SP and the BSP had not allied for the sake of the country or Uttar Pradesh.
"They know they cannot fight Modi on their own and their opposition to him is the sole base for their alliance," he told reporters on the sidelines of the party's national convention in Delhi.