The BBC's Sumit Bose reports on cancer targets

Some hospitals, such as the Beatson Oncology Centre in Glasgow, are currently taking up to nine weeks to see patients for treatment. This is well in excess of the Government's recommendation of a maximum waiting time of one month.

The warning comes after ministers announced they were extending to all cancer patients a commitment that all suspected breast cancer sufferers are seen within two weeks .

Health Secretary Alan Milburn last month also pledged an additional £50m to target heart surgery and the new NHS cancer supremo Professor Mike Richards has vowed to save the lives of 100,000 cancer patients over the next 10 years.

But cancer specialists told BBC Breakfast News these targets could not be met within existing resources.

Beatson Oncology Centre serves a population of 3m people but has only six radiotherapy machines. It should have 12.

Dr Nick Reed: 'Patients are already waiting too long'

Dr Nick Reed, clinical director at Beatson, said: "There are patients whose tumours have recurred within six to eight weeks. It has meant their treatment programme has had to be changed.

"Patients with throat cancer have finished up having a tracheotomy, which might have been avoided."

And Professor Jamie Weir of the Royal College of Radiologists added: "If we introduce screening programmes correctly, we pick up patients' cancer earlier.

"I don't have the resources, nobody has the resources in the UK, to keep to the two week waiting list time."

The government says it has provided £93m for new equipment this year, but doctors said 10 times that figure would be required.

The Scottish Executive said it was "aware of a problem with radiotherapy waiting times" at Beatson, but it was "a matter for the North Glasgow NHS Hospitals Trust".