Jessica Coakley Martinez hit out at the west London airport in an open letter published on Facebook, labelling the rules "incredibly unfair".

Restrictions from the Department for Transport for carrying liquid on to flights departing the UK have been in place since 2006 when a terrorist plot to detonate liquid explosives onboard seven transatlantic airliners was foiled.

However Martinez, who was not travelling with her eight-month-old son at the time, vented frustration at her treatment, saying: "You made me dump out nearly two weeks worth of food for my son,".

According to Heathrow’s website, exceptions are made for baby food and baby milk, but the passenger must be travelling with an infant.

It states that excess liquids should be carried as hold luggage in accordance with Department for Transport regulations.

Ms Martinez, who is from the US, admitted she should have checked the rules but believed that not allowing a mother travelling alone to take breast milk through security was "incredibly unfair and exclusionary in consideration of all of the other working mothers like me," the BBC reported.

She also revealed that more than 300oz of the 500oz milk (14.8 litres) "was frozen solid" but says she was ordered to dump that too.

"I was willing to let go of the liquid milk. But you also wanted the solid milk because it could ’melt and become a liquid’," she continued.

"I now don’t have the option to solely breastfeed my son because I don’t have enough milk to supply him while I’m at work, despite all of my best efforts. Security is the priority, but it isn’t and shouldn’t be your only goal, and it certainly shouldn’t punish those you intend to protect.

"Beyond literally taking food from my child’s mouth, you humiliated me and made me feel completely defeated as a professional and a mother."

Currently, rules state liquids may only be carried in containers holding 100ml or less in a transparent and resealable single bag.