Dr Sarah Jarvis has told Daybreak that it would be "difficult" to impose a seven-day rule on GPs and hospitals.
She said: "This is not going to be free, there's going to be a lot of bureaucracy and that means more cost for the NHS and patient care would suffer."
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Noticeably milder day, but rain heading in later this afternoon.
Prince Harry has shown off the results of his photography skills in a series of images he took on a charity trip to Kenya last week.
Oxfam have released a 10-year review accessing the impact of their work after the Tsunami.