A centre has released an urgent appeal for donors with special blood groups.

NHS Blood and Transplant has called for B negative and O negative blood donors to donate at the Edgwae Donor Centre.

The recent cold and freezing weather has meant fewer people have donated recently, and led to some cancelled sessions, meaning stocks of these valuable groups are lower than seriously ill hospital patients will need this Christmas.

O negative is a universal blood group that can be given to almost anyone, while B negative is important for those with serious blood disorders and is more common in black and Asian people.

Jon Latham, of NHS Blood and Transplant, said: "The recent poor weather has resulted in us having less O negative and B negative blood than is required for patients going into Christmas.

"If you are a donor with one of these important blood groups, please just walk into Edgware Donor Centre as soon as you can, and we will take your blood.

"Seriously ill patients in Edgware will need blood this Christmas and they will rely on the generosity of people making time to donate now."

To donate in Edgware, visit Edgware Donor Centre on Burnt Oak Broadway by Edgware Community Hospital.

Donors with in-demand blood types will not need to make an appointment, but call the donor line on 0300 123 23 23 or visiting www.blood.co.uk for more information.