Dutch airline KLM faced sharp criticism on Wednesday for its “antiquated values” after cabin crew told a breastfeeding woman to cover herself up to spare the blushes of other passengers.

Women’s rights campaigners reacted angrily when KLM confirmed the policy on social media, saying the company was playing into stigma and mothers should never be shamed for feeding their children.

“Negative attitudes about breastfeeding in public stem from the over-sexualisation of women’s bodies,” said Niki Kandirikirira from the advocacy group Equality Now.

“Breastfeeding is a totally natural process and women should have the freedom to do it wherever and whenever they want, rather than being forced to hide as if they are doing something inappropriate.”

The World Health Organization recommends that babies be breastfed exclusively for their first six months, then have a diet of breast milk and other food until they are two years old.

The furore started after a woman posting under the name Shelby Angel said on Facebook that a flight attendant told her to cover herself while breastfeeding her one-year-old on a flight between San Francisco and Amsterdam last month.

She said she refused, but was left feeling “uncomfortable and disrespected” and when she complained to KLM she was told the attendant’s response was in line with company policy.

“So instead of standing up for and protecting breastfeeding mothers and our children, already under the duress faced by flying with our young children, KLM would rather hold up antiquated values that shame women’s bodies,” she wrote.

When asked to confirm its policy on Twitter, KLM said it “permitted” breastfeeding but mothers might be asked to conceal themselves.

“To ensure that all our passengers of all backgrounds feel comfortable on board, we may request a mother to cover herself while breastfeeding, should other passengers be offended by this,” KLM said on Twitter.

However, Ayala Ochert from British campaign group Better Breastfeeding said breastfeeding in public was accepted in the “vast majority” of countries and the company was out of step with social norms.

“In their effort to avoid offence in the tiny minority of people disturbed by the sight of a child feeding, KLM has instead chosen to offend a mother trying to feed and nurture her child,” she told the Thomson Reuters Foundation.