Russell Goodway, the cabinet member for economy on Cardiff Council, told ITV Cymru Wales' Sharp End programme that Wales' largest local authority would also be struggling to balance the books after cuts to funding in the Welsh Government's Draft Budget.
He said: "We employ 10,000 full-time equivalent, excluding teachers. I doubt by the time we get to 2017 that half of those people will be working for the council."
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Wales Captain Sam Warburton says his team are raring to go as they kick off their Six Nations campaign in Dublin tomorrow.
Liberal Democrat leader Tim Farron has criticised Labour at the party's spring conference in Cardiff.
A Royal Gun Salute was held at Cardiff Castle earlier today to mark the 64th anniversary of the Queen's accession to the throne.