UP Bypolls: Mayawati's BSP had earlier allianced with the SP to form the government in 1993.

Highlights Mayawati's BSP has announced support to Samajwadi Party in UP

The two arch rivals have joined hands ahead of national election in 2019

The UP bypolls will emerge as the first test of an opposition alliance

Two bitter rivals In Uttar Pradesh, the Samajwadi Party and Mayawati's Bahujan Samaj Party (BSP), have joined forces to confront the ruling BJP and its Chief Minister Yogi Adityanath on his home turf Gorakhpur. BSP leader Ghanshyam Kharwar today confirmed that his party will support Samajwadi Party in the bypolls.While Akhilesh Yadav is yet to make an announcement on what is seen as the first major political realignment ahead of the national election, a tweet by SP spokesperson Pankhuri Pathak has indicated collaboration between the arch rivals."BSP to Support @samajwadiparty in the LS By-Polls in Phulpur & Gorakhpur . Much awaited decision by Mayawati Ji . Looking forward to contesting together & creating a larger Bahujan secular alliance ," the tweet from yesterday read.Bypolls in Gorakhpur and Phulpur Lok Sabha constituencies vacated by Yogi Adityanath and his deputy Keshav Prasad Maurya will be held on March 11. The ruling BJP, which won over 300 seats in the 403-member UP assembly last year, expects a walkover.But the bypolls may emerge as the first test of an opposition alliance that has been talked about since the BJP's massive mandate in 2014 and all its subsequent state election victories, including in UP.The SP and BSP had earlier contested the 1993 UP assembly elections together to halt the rise of the BJP. In the new government, Mulayam Singh Yadav became the chief minister, but the relationship soured and BSP withdrew support in less than two years. Mayawati came to power with the help of the BJP in 1995.The BSP, which was reduced to just 19 seats in the 2017 assembly elections, is not contesting this bypoll. The Samajwadi Party and the Congress, which fought last year's assembly polls together without much success, have declared their candidates.Yogi Adityanath, 45, held the Gorakhpur Lok Sabha seat for five straight terms. He had secured over 50 per cent vote share in the last three elections, and is the party's face in this bypoll. He has been aggressively campaigning for the BJP's Upendra Dutt Shukla. It is Mr Shukla's first election.Keshav Prasad Maurya was a first-time Lok Sabha member from Phulpur, a seat the BJP won for the first time in 2014, riding the "Modi wave". The constituency, once held by former Prime Minister Jawaharlal Nehru, had come to be known as a stronghold of Mayawati's party before the BJP's win.

Praveen Kumar Nishad of the Nishad Party, which represents the backward classes Nishad group which has a significant presence in Gorakhpur, has been fielded by the Samajwadi Party. SP chief Akhilesh Yadav is expected to campaign for him in the last few days before the bypolls.Before the alliance, Mr Nishad, an engineer by profession, had hoped if Ms Mayawati offered her support, "together they can fight the communal forces effectively".