The Shadow Health Minister Darren Millar described the figures about ambulance response times in 2012 as "shocking" and "inexcusable".
He said "we have a big problem in the way that our emergency care system is operating in Wales", both in terms of ambulances and A&E departments.
The Welsh Government has commissioned a review into how emergency response times can be improved, which will report next month.
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Any rain will eventually clear this afternoon, bringing brighter weather behind it.
Public Health Wales are warning visitors to be aware of the infectious diseases associated with livestock this bank holiday weekend
A band of rain pushing in overnight, bringing with it the odd spot of coastal and hill fog, but things should improve by tomorrow.