The agency said that despite the huge influx of humanitarian goods into Gaza during phase one of the ceasefire which began on 19 January, it has not been enough to make up for the 15 months of war when supply convoys were frequently blocked, impeded or cancelled by the Israeli military.

Speaking from Gaza, UNICEF’s Rosalia Bollen said that being unable to bring humanitarian relief into the enclave including vaccines and ventilators for pre-term babies “will have devastating real-life consequences” for children and their parents.

“If we’re unable to bring that in, routine vaccination will come to a standstill”, she told UN News. “Neonatal units won’t be able to care for preterm babies, so this is a real-life consequence that we’ll be dealing with very, very soon if we’re unable to resume the aid supplies coming in.”

The UNICEF Communication Specialist said that existing aid supplies have already been largely distributed throughout Gaza.

“The needs are so high that we haven’t been able to stockpile goods...that's why these latest restrictions are so devastating," she said, adding that the first phase of the ceasefire wasn’t just a pause in hostilities…it really was a lifeline for families here...The mood here is very depressed; families that I speak with are deeply worried about what the future is going to hold."

Nutrition gains reversed

The aid blockade comes as the UN aid coordination office, OCHA, reported a slight improvement in dietary diversity during the ceasefire which humanitarians says "is now being reversed" by the aid blockade.

Before the current conflict, acute malnutrition in Gaza was almost non-existent, but today more than 3,000 children and 1,000 pregnant or breastfeeding women have been referred for acute malnutrition treatment.

In a more positive development, OCHA noted that February showed a slight improvement in the number of children and pregnant and breastfeeding women consuming the minimum required food groups.

Citing assessments by nutrition partners, the UN aid office added that about eight per cent of children consumed four or more food groups and there was “a noticeable increase in the consumption of fruits, vegetables, eggs and dairy products”, indicating increased availability at local markets.

The ceasefire between Hamas and Israel had allowed aid organisations such as UNICEF to scale up urgently needed supplies for children and their parents in Gaza. These items included vaccines for routine immunisation, disposable medical supplies for hospitals, along with syringes, gauze and specialised equipment such as incubators, and ventilators to help pre-term babies breathe.

Other fundamental repairs had also been started to rehabilitate smashed public infrastructure, too.

"We had just managed to start increasing water production, especially in the north, " said Ms. UNICEF's Ms. Bollen. "We've been repairing water wells, we've been increasing distribution possibilities. All of that will be coming to a standstill."