It is the worst nightmare a parent could ever endure.

Loua Al Shaikh has kept watch at his daughter Zara's bedside as she bravely battles a potentially deadly blood cancer.

Now the Hampshire dad has made an impassioned plea for help in the "race against time" to save the teenagers' life and find a matching stem cell donor.

His desperate call comes as a widespread donor recruitment event is launched in the schoolgirl's home city of Winchester on Saturday in the hunt to find a match for the aspiring young artist.

Zara, 13, urgently needs a blood stem cell donation to treat a form of leukaemia but has struggled to find a match due to her heritage being half English and half Arabic.

The King's Secondary School pupil, who is currently being cared for in Southampton General Hospital, was diagnosed with myelodysplastic Syndrome (MDS) in May 2014 and endured four courses of chemotherapy before going into remission.

But in January this year the cancer returned and her best chance of survival is to undergo a bone marrow transplant.

This week the teen - who is an avid Manga and animation fan - completed another session of chemotherapy which has caused her hair - which she especially dyed blue before the treatment - to fall out.

Mr Al Shaikh, 55, who has been at her bedside with her mother Kerensa, 46, and younger sister Claudia, 12, said: "Somebody out there is her match and it's about finding that somebody.

"We want somebody to come forward whoever they are where they are to save Zara's life. There's somebody out there walking along a high street, on a mountain, or even in a desert. But until they get tested they don't know."

He likened the search as a "race against time" and explained that donors from many different heritages and nationalities could have compatible tissue types.

Mr Al Shaikh, himself an intensive care consultant, who was born in Iraq, said: "It's very difficult to go from professional care to be on the receiving end of a career you have devoted yourself to and to see your own flesh and blood being treated for such a serious disease. She was such a healthy and studious young lady and so bubbly and creative. You don't know how these things affect you until they hit you."

He hailed the Southampton General Hospital staff and those at University College London (UCL) where the future transplant is likely to take place as "the dream team" of oncology services.

He said: "This isn't hopeless. We have to remain positive. The support we've received from our wider family and friends is unbelievable. We believe she is going to smash this.

"She is a strong and determined young lady who we believe has an amazing future ahead of her in art."

Delete Blood Cancer UK is spearheading the search by organising a donor recruitment event on Saturday where people are invited to swab the inside of their cheeks to register as potential donors.

Charity spokeswoman Jenny Clegg said: "Registering as a potential blood stem cell donor is so easy. It takes minutes but it could lead to you saving someone's life. Please come along and register to help find a matching donor for Zara."

The event takes place from 10am-4pm in St Peter's Roman Catholic Church in Jewry Road, Winchester.

If you are unable to attend register online to request a cheek swab kit at deletebloodcancer.org.uk