Chris Sheldon, Chief Executive of the Kingdom Bank, an independent Christian bank, said the government's decision to sell part now had to be looked at from a wider perspective.
Chancellor George Osborne announced he had started returning Royal Bank of Scotland into private hands with a £2.1 billion share sale.
He faced criticism for the move which has left the taxpayer short-changed with a £1 billion loss.
Mr Osborne insisted the move was the "right thing to do for the taxpayer", coming seven years after the Government rescued RBS with a £45.5 billion bailout at the height of the financial crisis.
It marks a milestone moment for the banking sector as it puts the crisis behind it, while it also kick-starts the Treasury's plans for a bigger privatisation programme than in the 1980s with aims to raise more than £30 billion by the end of next March.
But concerns have been raised over the timing of the Treasury's decision to sell-down its 78% stake in RBS after the taxpayer has been left nursing a £1.08 billion loss.
Mr Sheldon told Premier: "You've got to look at this in terms of the timescale over which its being proposed.
"Yes this first tranche is being sold at a loss but it's the start of a process and we don't know at this stage whether at the end of that process there will actually be a profit."
Chris Sheldon speaking to Premier's Antony Bushfield: