Though, both the parties have recently come closer, particularly after they together managed to win the Lok Sabha by-elections in Gorakhpur and Phulpur, their leaders have not been seen together on a public platform yet.
"Akhilesh Yadav has got an invitation to attend the oath-taking ceremony in Bengaluru and will attend it, Samajwadi Party spokesman Rajendra Chaudhary said. Meanwhile, a BSP leader confirmed Mr Kumaraswamy had yesterday met Mayawati in New Delhi and that she will also be attending the function
"This could well be the beginning of new ties between the two parties who have already shown the strength of their unity," an SP leader said, indicating that they are working with the 2019 Lok Sabha election in mind.
After their win against the BJP in in Gorakhpur and Phulpur, the opposition in UP is also fighting the May 28 by-election in Kairana together. The SP and the BSP are backing the Rashtriya Lok Dal candidate in that Lok Sabha constituency.
Mr Kumaraswamy's swearing-in ceremony is being projected as a show of strength by non-BJP parties. Delhi Chief Minister Arvind Kejriwal and West Bengal Chief Minister Mamata Banerjee are among the leaders invited to the ceremony.
Mr Kumarawasmy will form the government with the backing of the Congress after the May 12 assembly elections delivered a split verdict in Karnataka.
B S Yeddyurappa was sworn in as chief minister after the BJP emerged as the single largest party in the election, but he resigned ahead of the floor test in Karnataka assembly.