Party sources said Ilmi was unhappy with the party leadership on certain issues, including the choice of her Lok Sabha constituency Ghaziabad from where she had unsuccessfully contested.
Ilmi, a journalist who has been with the AAP since its inception, had conveyed the party leadership her desire to contest from one of the seven seats in Delhi in the Lok Sabha elections.
The AAP leader is expected to address media on Saturday.
Ilmi, a popular minority face of the party, had also lost Delhi assembly elections from the R K Puram constituency.