There are growing fears the rising price of baby formula is leading to parents watering down feeds or giving infants ‘unsafe alternatives’.

Charities say the UK is on the brink of a public health crisis caused by the escalating cost of baby milk that means the cost of feeding a 10-week old baby is now close to £90 a month.

Organisations say they have ‘serious concerns’ about infant health and family finances after the latest monitoring of formula prices suggest costs have risen by an average 24% in two years.

The only ‘own-brand’ infant milk available to buy increased by 45% in the same period, says the report.

With families reportedly being driven to increasingly extreme measures - such as altering the quantities of feeds or buying cheaper out of date milk on a black market, trust First Steps Nutrition is calling for the government to step in and cap prices.

Dr Vicky Sibson, director, explained: “Families least able to afford formula are the most likely to need it and it is a really expensive food whose price keeps rising. That infant formula may simply be unaffordable for some with babies is deeply concerning as some of the coping stragies they feel forced to use may harm their baby’s health.

“As all first infant formulas are, by law, nutritionally comparable there is also no excuse for the very wide range in prices between different products.”

Suppliers blame rising costs of production, transportation and storage for price increases.

As the cost of living crisis has deepened some supermarkets have resorted to adding security tags to formula packaging or putting it behind counters.

Neil Charlick, chief executive of food bank Gillingham Street Angels says those reliant on his service are really struggling and he wouldn’t be surprised to see crime rise as a result.

The organisation, which has this week taken delivery of a substantial donation of infant formula which is now being made available to families, is equally concerned about the measures parents could be driven to in order to feed their offspring.

He added: “They could be putting the babies in danger giving it the wrong kind of thing.

“People are struggling out there across the board in a number of different ways.”

Alison Thewliss, chair of the all-party parliamentary group on infant feeding and inequalities, said an increase and expansion to Healthy Start payments, which help families claiming certain benefits buy nutritious food and milk also now needs to be considered.

She said: “It is clear that families are paying over the odds for an essential product. That could lead to parents watering down formula or feeding babies unsafe alternatives with a long term impact on health and development.

“DEFRA must step in to cap the soaring cost of formula, Furthermore Health Start payments must increase to reflect the rise in inflation and expand to make sure all families are able to access them.”