The models responded with gusto, sharing photographs of themselves with squeaky clean faces, pouting and smiling into the camera.

Twenty-five-year-old Miss Australia Monika Radulovic pulled her brunette hair into a high ponytail and grinned broadly at the camera sans slap while Miss Ireland Joanna Cooper, 21, puckered up and blew her fans a kiss.

Keen to show her support for the campaign, Miss Dominican Republic Clarissa Molina, 24, washed off her berry-hued lip tint and smoky eye make-up to proudly show off her natural complexion.

Meanwhile, Miss Bahamas Toria Nichole Penn, 27, took her slap-free selfie early in the morning. Showcasing a halo of curls and a wide smile, she captioned the picture, 'Preliminaries today! Woke up fresh faced and ready to do this!'

Twenty-four-year-old Miss Peru Laura Spoya looked strikingly similar to Victoria's Secret Angel Alessandra Ambrosio in her bare-faced portrait while Miss Ghana Hilda Frimpong, 26, looked more youthful without all the contouring and cherry red lips.

Stunning brunettes Miss Ecuador Francesca Cipriani, 23, and Miss Argentina Claudia Barrionuevo, 24, also proved they're beautiful without loads of make-up.

Stunning brunette Miss Ecuador Francesca Cipriani, 23, confidently posed with her lipstick and mascara