The father of a four-year-old leukaemia sufferer given just weeks to live has made a heart-felt plea to doctors to give his son one last chance of life.

Charles Afolabi, 49, from Harrow, north London, wants doctors treating his son Tomi to try him on last resort drug nelarabine which is used in the US for patients who have not responded to chemotherapy. Mr Afolabi and his wife Gloria, 39, have been told that the little boy has only three to six weeks to live, yet the medical team do not want to put Tomi on the drug because they claim it could kill him.

Mr Afolabi found out about the drug by searching the internet for possible cures after the medication that was keeping Tomi in remission stopped working. Initially doctors were looking at the possibility of treating Tomi with the drug but warned him it could cause convulsions and neurological problems.

They told him about a trial that was being run by pharmaceutical firm GlaxoSmithKline.

However, as Tomi's condition deteriorated they said he was too poorly to take part. Mr Afolabi is pleading with doctors to change their mind and agree to put his son on the trial despite the risks.

"On Saturday they said my son's condition is so bad that it could kill him. But he has got three to six weeks to live. What is there to save?" he said yesterday.

Tomi was diagnosed with leukaemia in March last year.