Richard Darlington, from the Institute for Public Policy Research, commented on the organisation's survey suggesting 41,000 extra under-25s will be out of work this year.
"I'm afraid that the signs for the economy according to the Office for Budget Responsibility is that the slowdown is going to continue." he said.
"Unfortunately, unemployment tends to lag the rest of the economy and we're not going to see unemployment fall in Wales until about 2013."
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Wales have qualified for the Euro 2016 quarter finals after beating Northern Ireland 1-0 in Paris.
A rally has been held in Cardiff following the EU referendum to show support to migrant communities.
It's 0-0 at half time in Paris as Wales face Northern Ireland in the last 16 of Euro 2016.