Mayawati has proved that she has no self-respect, the BJP leader said. (File)

A day after his controversial remarks against Congress president Rahul Gandhi and his sister Priyanka Gandhi, BJP MLA Surendra Singh has accused BSP president Mayawati of "murdering" a woman's dignity by joining hands with one-time arch rival Samajwadi Party.

"For power, Mayawati has done what no person who values his or her dignity would do... she has embraced those who had attacked her and by doing so she has murdered a woman's dignity," Mr Singh told reporters at his residence on Wednesday night.

He was referring to the infamous 1995 state guest house incident in Lucknow in which Mayawati was attacked by Samajwadi Party workers.

One may or may not achieve success, but by allying with those who had trampled upon her prestige, Mayawati has proved that she has no self-respect, said Mr Singh, who represents the Bairia assembly constituency of Uttar Pradesh.

He claimed that only position and self-interest mattered to Mayawati and not if the other person had used foul language against her or harmed her dignity.

The BJP MLA had on Tuesday compared Rahul Gandhi and Priyanka Gandhi to Ravana and Surpanakha respectively - the villains in Ramayana.

Mr Singh's remarks invited angry reactions from the local Congress workers and swift disapproval from Union Minister Mahesh Sharma on Wednesday.

Earlier, he had backed his party colleague and MLA Sadhana Singh after she called Mayawati "worse than a transgender".

"There is nothing wrong in what Sadhana Singh said... any person who has zero self-respect is called a transgender," he had said.