Suzanne Evans has told talkRADIO that the "wilful blindness" towards radical Islam must be tackled.
Speaking to Julia Hartley-Brewer in the studio, Evans said Islamist terrorism is now the biggest threat to UK security, adding "as a woman I find it absolutely abhorrent the way in which we have cultural practices that have been introduced to Britain that did not exist when I was a child."
She went on to condemn female genital mutilation and honour killings, while claiming "we've had a blind eye turned to the appalling sexual abuse of white girls.
"There is a wilful blindness and a blinkered approach to this, we have to tackle it."
Evans also said UKIP has been the most successful British political party in the 21st century, and gave her views on fellow leadership challenger Paul Nuttall.
Listen to the interview by clicking above