The chief minister of India's most populous state, Uttar Pradesh, says she has handed in her resignation.
Ms Mayawati had earlier denied she had resigned
Ms Mayawati made the move the day after the break up of the governing coalition between her Bahujan Samaj Party (BSP) and its junior partner, the Bharatiya Janata Party (BJP).
The governor now has to decide whether to impose direct rule over the state and suspend the assembly, call fresh elections or invite other parties to form an administration.
UP is politically India's most important state, sending the largest number of lawmakers to the national parliament.
'Ready to defect'
Ms Mayawati told journalists on Tuesday that other parties were already arranging deals to form an alternative administration.
The biggest party in Uttar Pradesh, the Samajwadi Party, has asked the state governor to let it try to form a government.
The party, led by Mulayam Singh Yadav, has 142 seats in the 403-seat assembly.
Ms Mayawati says at least 40 members of the BJP were ready to defect to the opposition.
She also said she was not interested in running a caretaker government and that she was not "hungry for power".
While she has called for fresh elections, the BJP is against dissolving the present assembly.
Other opposition parties are supporting the Samajwadi Party's efforts to form a new government.
The BSP, whose power base is among lower caste Hindus, agreed to share power with the BJP after inconclusive state elections last year.