Flu vaccinations for thousands of primary school pupils in the north-east of Scotland have been delayed.

A UK-wide issue means supplies of the nasal spray Fluenz Tetra will not arrive in the region in November.

The Scottish Government had previously warned of potential delays, but now NHS Grampian has confirmed most vaccinations have been postponed until December.

A spokeswoman for the health board said: "There is a UK-wide issue affecting the supply of the child flu vaccine - the nasal spray called Fluenz Tetra.

"It means we will not receive all of our scheduled supply of the vaccine during November.

"The Scottish Government has advised us to prioritise our remaining existing stock of the vaccine to children aged between two-five years who are not yet in school and those aged 5-18 years with underlying health conditions as these children are at greatest risk from the flu virus and this is the course of action we will follow.

"Unfortunately, this means we will be unable to offer vaccination to all pupils in the vaccination sessions scheduled to take place in primary schools from November 6 to early December.

"Those scheduled sessions will still take place but vaccination will only be offered to those pupils who have underlying health conditions."

The delays are down to issues with routine testing of the vaccine by its manufacturer.

The Scottish Government's deputy chief medical officer Gregor Smith said: "I would like to reassure parents and families that we are doing everything possible to minimise any disruption caused by the delay in supply of Fluenz Tetra.

"We are working with Public Health England, Health Protection Scotland, NHS boards, and other relevant partners to ensure that all eligible children get their flu vaccine as soon as possible.

"Those most at risk and children aged two to five-years-old will be prioritised initially, with boards working to ensure all other eligible children, such as those at Primary School, receive their vaccine in due course."

Manufactuer AstraZeneca said in a statement: "AstraZeneca confirms there will be a delay in the planned release and delivery of a portion of our Fluenz TetraTM (Live Attenuated Influenza Vaccine) doses in the UK for the 2019-2020 season.

"In order to comply with regulatory requirements for the distribution of vaccines, there are number of tests that need to be performed before vaccines are released."