Scottish Liberal Democrat MSP Willie Rennie lambasted disagreements over the issue in Holyrood.
It came as party leader Alex Cole-Hamilton pressed the Scottish Government on the legal advice it had received on holding another referendum.
Mr Rennie asked about the Government's policy on currency in an independent Scotland.
SNP constitution secretary Angus Robertson replied: "Scotland will continue to use the pound sterling at the point of independence, establishing an independent Scottish currency as soon as is practically possible through a careful, managed and responsible transition when an independent Scottish Parliament chooses to do so."
Mr Rennie said the SNP leadership wanted a monetary union in 2014 and now backs "sterlingisation".
However, the SNP conference previously rejected the leadership's timeline, while Green co-leaders Lorna Slater and Patrick Harvie, who are now Scottish Government ministers following a power-sharing agreement, have a different view.
Mr Rennie said: "Alex Salmond wants a Scottish pound. [SNP MP] Alyn Smith wants the euro.
"The independence movement is like two bald bankers fighting over a 50p piece.
"If they can't agree on the currency, why on earth should the public?"
Mr Robertson replied: "There is literally no answer that I could give to Willie Rennie that would satisfy him.
"We are on different sides of the independence debate.
"If we can't agree on that, at least it would be nice for us to be able to agree as democrats that this is an issue that the people should be able to decide on."
Mr Cole-Hamilton asked if the Government had published all the legal advice it has received in relation to a second referendum.
Mr Robertson said it had released the advice required by a recent ruling from the Scottish Information Commissioner, “as it does not merit the time and expense required for an appeal”.
This followed a Freedom of Information battle with The Scotsman.
Mr Robertson added: “In line with the ministerial code, I do not intend to comment on the content of other legal advice.”