The party's decision came on the day the Supreme Court took a serious note of the incident and ordered that all the cases pertaining to rape and the road accident of the victim will be investigated in New Delhi, not Uttar Pradesh.
BJP MP and spokesperson G.V L Narsimha Rao said that there is no place for any person in the party who is facing serious charges.
Sources said that the party was forced to take action against the MLA because of growing public outrage and the tough stand taken by the SC sealed Sengar's fate.
The party had earlier refrained from taking stern action as the legislator was seen to be close to Uttar Pradesh Chief Minister Yogi Adityanath. Party leaders said that now defending him had become untenable in wake of the growing sentiment both outside and within the party.
Representing Bangarmau assembly constituency in Unnao, Sengar had joined the BJP in 2017. It had taken immense pressure for the BJP to ensure Sengar is arrested after he was accused of raping a woman in Unnao.
The rape victim is battling for her life after being seriously injured in a road accident on July 28 near Rae Bareli. Sengar, who is in jail, is under scanner for his alleged role in the accident in which victim's two aunts died and her lawyer got seriously injured.
He has been in all the political parties in Uttar Pradesh starting with the Congress, then joining the Bahujan Samaj Party before having a stint with Samajwadi Party and finally landing in the BJP.
UP BJP chief Swatantra Dev Singh on Wednesday had said that Sengar was under suspension amidst growing demands for his expulsion. Sources said that his political clout in the region forced BJP to delay the decision to expel him.
( With inputs from IANS )