Former Northern Ireland secretary Mo Mowlam deliberately misled then British Prime Minster Tony Blair about her brain tumor before she took over the job of Northern Ireland secretary, it has been revealed.

A new film, based on the evidence of her doctor who has agreed to release the medical information, will make clear that Mowlam was far sicker than anyone thought when she played a key role in the Northern Irish peace process. Her husband authorized the doctor to release the information.

Mowlam, who died from the tumor in 2005, was actually told in1996 by her doctor, Mark Glaser, that her brain tumour was malignant and that she had about three years to live . Yet she told Blair and political colleagues that it was benign.

After Labor's 1997 victory Mowlam was made Northern Ireland Secretary and played a major role in moving the Irish peace process forward. She was known for her informal style, and on several famous occasions, taking off the wig she wore because of chemotherapy in important meetings.

Dr. Glaser told the film-makers that Mowlam had "deceived me" by not telling the truth to the Prime Minister. "A frontal-lobe tumour can cause disinhibition, behavioural disturbance and poor judgement. And there she was taking up a job in what was effectively a war situation.

"But there was nothing I could do. I was her doctor. I was responsible for her care, even if she wouldn't let me keep records in the proper places or write to her GP. I told her to tell Blair, but she didn't, she lied. So I went the extra mile for her because she demanded it from me. I was trapped... She was doing this very important job, one that affected so many people's lives, while she was ill; but she was also my patient and I owed her confidentiality."

During the 1997 election campaign, Mowlam only revealed that she had been suffering from a "benign" tumour.