Bishop Mulakkal is accused of raping a nun on 14 occasions from 2014 to 2016.
A nun from Kerala's Wayanad, who was part of a protest against rape-accused Bishop Franco Mulakkal, was issued a final notice by church authorities and asked to leave the congregation. She had earlier been issued two warning letters.
In its notice, the Franciscan Clarist Congregation accused Sister Lucy of leading a life which was against the "principles of religious life" and the rules of the congregation. She has been asked to give an explanation to the Superior General Sister at Generalate of the Congregation before April 16, news agency PTI reported.
Sister Lucy said she is saddened by the church's accusations. "I joined the church when I was 17. I have lived a life following all the principles of religious life. I don't have any other life. My reply to the second warning letter earlier was very clear. I have explained my stand," she was quoted as saying by news agency PTI.
The nun had received two warning letters from her superiors in the Catholic Church in January. In the first warning letter, she had been asked to explain why she had acquired material possessions and belittled Catholic faith.
The congregation has termed as "grave violations", Sister Lucy's obtaining a driving license, buying a car and publishing a book without permission and knowledge of her superiors. It also objected to her participation in TV discussions and writing of articles for non-Christian newspapers.
Bishop Mulakkal is accused of raping a nun on 14 occasions from 2014 to 2016. Four nuns have rallied behind the complainant.
(With inputs from PTI)