Laura Anne Jones has demanded answers from the Welsh Government after the Finance Secretary Mark Drakeford ordered a review into income tax rates in Wales.
The review will look at the possible benefits of switching to a Scottish-style model of taxation, where different rates hit middle-income earners harder.
The South Wales East Senedd Member has urged the Welsh Government to drop any plans to raise more taxes from working people.
Ms Jones has tabled a question to the Finance Secretary asking for clarity on the plans.
Currently, the Welsh Government can vary income tax, but only under England’s basic, higher and additional income tax bands.
The Scottish Government has introduced further income tax bands, placing higher rates on middle earners.
For instance, in Scotland, people who earn between £26,562 and £43,662 in Scotland are charged an intermediate rate at 21%, when in England they would be charged the 20% basic rate.
A study by HMRC showed that thousands of taxpayers left Scotland after the tax raid.
Laura Anne Jones MS, Senedd Member for South Wales East and Shadow Minister for Housing, Local Government and the Armed Forces, said:
“This dreadful plan from the Welsh Government is bad for Wales and for household budgets in Wales.
“After inflation-busting council tax rises across much of Wales, this cloak and dagger tax rise will place additional hardship on hard-pressed taxpayers.
“The Welsh economy is already sadly the worst in the UK, with some of the worst wages in the UK, and raising income tax will be the final nail in the coffin of the Welsh economy.
“We should be cutting taxes and attracting people to Wales, not milking them dry with fresh taxes.”