School food expert Prof Kevin Morgan said it needs to look at increasing the price per meal given to local councils.

Education Minister Jeremy Miles said it is looking at the unit price.

It was set with "an assumption about possible increases in costs", he added, saying: "The world has obviously moved on and we are doing a review."

At the moment, Welsh councils get about £2.90 per child per meal for primary school meals.

This price was set before the new universal school meals policy was started last September.

Prof Morgan told the BBC's Wales Live "that £2.90 is no longer a viable rate in my view".

"That obviously needs to be looked at again," he added.

He said it was important that the food available for children was attractive and high quality to reduce waste.

Universal free school meals will be rolled out in phases to primary school pupils across Wales

Brad Pearce, the national chairman of the Local Authority Caterers Association, painted a difficult picture for school caterers across Wales.

He said members had seen increases of 20% on the price of things such as milk, cheese, meat, fruit and vegetables.

"Cumulatively we'll have seen increases between 50 and 70% since May last year," he added.

'Local, fresh produce'

Mr Pearce said the funding per meal needed to rise with inflation to enable caterers to buy good quality produce.

He said: "We need those to be reviewed and addressed... to take into account the increase in food costs so we can buy the local, fresh produce to produce the best quality meals."

According to the Office for National Statistics, food inflation has increased by nearly 5% since September.

Universal free school meals are being rolled out in phases to all primary school pupils in Wales, as part of a co-operation agreement between the Labour Welsh government and Plaid Cymru.

"It needed to be a whole school approach, with the additional workload that it's brought," says head teacher Gayle Major

By April, every child in reception, Year One and Year Two was supposed to have been offered a free school meal.

Most schools in Wales have reached that target, but not all.

Despite this, the education minister said he was confident the target of offering all primary school pupils a school meal would be reached by April 2024.

'Incredible achievement'

"The effort which has gone into delivering this policy amongst local authorities right across Wales has been mammoth," said Mr Miles.

"By next year every child in a primary school in Wales will be offered a nutritious hot meal which is an incredible achievement."

At Blaenhonddan Primary School in Bryncoch, Neath Port Talbot, staff said the rollout had been hard work but a success.

Head teacher Gayle Major said parents were "absolutely delighted" with the new policy but there were "significant challenges" to get it started.

"It needed to be a whole school approach, with the additional workload that it's brought to the school, the willingness of the staff within the kitchen and within my own staff to take on the extra responsibility has enabled it to be a success," she said.

"The school has taken on two extra permanent members of staff to cope with the increase in demand."