India's "Dalit Queen" Mayawati on Tuesday (July 18) quit the Upper House of Parliament amid an ongoing tussle with the ruling party to woo her voter base of Dalits, formerly known as untouchables.

Ms Mayawati, 61, whose Upper House term is coming to an end in April 2018, dramatically walked out of the Upper House after saying she wasn't given enough time to speak about atrocities against Dalits and minorities.

She accused the ruling party Bharatiya Janata Party (BJP), which has a majority in Parliament, of muzzling the opposition.

"I was not allowed to speak. When I can't put forward my views, I don't have any right to stay in this House, so I have taken this decision to give my resignation," she told Indian media personnel outside Parliament.

She sent her resignation letter to Vice President Hamid Ansari, who is the chairman of the Upper House.

Ms Mayawati, leader of the Bahujan Samaj Party and former ruler of India's most populous state Uttar Pradesh, was the undisputed leader of the Dalits. But her influence has been on the wane in recent years amid the growing influence of the BJP led by Prime Minister Narendra Modi.

Her party performed poorly in the 2014 general election and in the recently-held elections in Uttar Pradesh early this year.

After her term expires, she has little chance of getting reelected as her party has only 19 legislators in the Uttar Pradesh assembly. Candidates to the Upper House are elected by state assemblies.

On the other hand, the BJP's outreach to the Dalit community has seen the party fielding Dalit candidate Ram Nath Kovind for the presidential elections. Opposition parties followed by fielding their own Dalit candidate in Ms Meira Kumar.

Dalits remain at the bottom of India's caste hierarchy and continue to face social stigma and poverty across India.

Still, they remain an important political grouping wooed by various political parties.

Political analysts said that Ms Mayawati's threat to quit was aimed at scoring political points within her own community.

"She is trying to find a niche for herself for 2019 (general elections)," said Dr Aftab Alam, associate professor of political science of Aligarh Muslim University. "It's a battle of survival for her."