Scottish tycoon Sir Tom Hunter has called for proposed rises to National Insurance contributions to be reversed.
The government is planning to increase NI for employers and workers by 1p in the pound from April 2011.
The Conservatives pledged to reverse the increase for those on incomes under £45,000, if they win power.
A spokesman for Sir Tom said: "He believes the NI proposals should be reversed, hence he's neither supporting Labour or the Conservatives' policies."
The spokesman added: "Furthermore he believes the Scottish Parliament should use their tax varying powers to reduce the tax burden now, growth will come from stimulating the economy not punishing it with additional tax burdens."
The Tory plan has won the backing of 23 business leaders, who wrote a letter to The Daily Telegraph endorsing the move, saying that it "would protect jobs and support the recovery".
The signatories include Marks and Spencer executive chairman Sir Stuart Rose and Sainsbury's chief executive Justin King.
Sir Tom, 49, who describes himself as "resolutely apolitical", is a multi-millionaire businessman and philanthropist.
He is the founder of the private equity partnership West Coast Capital, which owns the high street chains Office and USC, and has pledged to invest £35m in education and enterprise across Scotland through The Hunter Foundation.
The director of CBI Scotland, Iain McMillan, said it was inevitable the rises in National Insurance would cost Scotland jobs.
He said: "If the rises go ahead from next April then it will be more expensive for businesses to employ people.
"That is not opinion, it is a fact.
"Therefore fewer people will be employed and fewer people will be kept in employment ."
Mr McMillan called for public spending to be "reined in" and for taxes not to be increased.