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.
More top news
The abbot of Caldey Abbey has apologied after it was alleged one of the island's monks sexually abused children in the 1970s and 80s.
Heavy rain and strong winds will continue this evening and overnight. By dawn, skies will clear allowing a colder, drier day tomorrow
'Get in early' is the warning from the Wales Rugby Union ahead of this weekend's clash between Wales and New Zealand.