Robin Gibb has defied the odds and woken up after spending a week in a coma, doctors told the press on Sunday.

His medical team attributed his  'iron will' to his progress, but his overall recovery still remains uncertain as he continues to receive treatment for cancer and pneumonia.

Only three days ago, I warned Robin's wife, Dwina, son, Robin John, and brother, Barry, that I feared the worst, Dr Andrew Thillainayagam, of Imperial College Healthcare, said in a statement on Sunday. We felt it was very likely that Robin would succumb to what seemed to be insurmountable obstacles to any form of meaningful recovery. As a team, we were all concerned that we might be approaching the realms of futility.

It is testament to Robin's extraordinary courage, iron will and deep reserves of physical strength that he has overcome quite incredible odds to get where he is now, his doctor added.

Gibb started to show progress this week, after his brother Barry Gibb started singing to him and playing music. The 62-year-old singer's eyelids started to flicker and later he started to move his head, according to the Daily Mirror.

The ECG scanner showed that Robin was responding to the music being played to him, Dwina revealed. We're very pleased. We think he might even talk once the tubes come out, she added.

Before falling ill, Gibb was supposed to make an appearance meant to perform at the premiere of Titanic Requiem on Tuesday, which he composed with Robin-John. His wife has been finding strength in the past week through listening to his latest work Don't Cry Alone, according to the Daily Mail.

Gibb was first diagnosed with cancer 18 months ago, when he was undergoing bowel surgery. The doctors found a tumor and diagnosed him with cancer of the colon and later with cancer of the liver.

His friends revealed that the 62-year-old had a bucket list, which he kept by his bedside at the hospital. One of Gibb's main wishes before he dies is to set up a children's charity involving music, his friend told the Daily Mirror.

Gibb was born in England in 1949. He founded the Bee Gee's with his twin brother Maurice and moved to Manchester to start performing. The Bee Gees released their first record in 1963. The brothers rose to fame for their hit records Jive Talkin, Stayin' Alive and Night Fever.

Robin Gibb's most recent performance was sin February, when he took to the stage to support an injured serviceman and women at the Coming Home charity concert in London.