The Scottish Parliament could be given the power to raise up to £10 billion under plans to extend financial responsibility, the Scottish Secretary has said.
Michael Moore said the Scotland Bill will be published in the next few weeks detailing the potential doubling of revenue-raising power.
The proposed legislation is expected to implement the recommendations of the Calman Commission, which investigated how devolution can be altered 10 years after the creation of the Holyrood Parliament in Edinburgh.
Mr Moore said: "The Scotland Bill will be published shortly and it will be the start of the largest transfer of fiscal powers out of London since the creation of the United Kingdom.
"We are going to increase the financial power and accountability of the Scottish Parliament."
The Liberal Democrat minister said MSPs do not have enough say in how the Scottish budget is raised.
Under the present arrangements, Scottish ministers are given a sum determined by the UK Government at Westminster.
Scottish Finance Secretary John Swinney will unveil details of his spending plans at Holyrood on Wednesday.
The SNP administration wants total control over finances but Unionist parties pushed for an extension of powers, short of independence.
Mr Moore said: "Next week the Scottish Parliament will start the process of deciding how to spend next year's budget. But at the moment they don't have enough say over how that budget is raised. That is a serious weakness that the Scotland Bill will fix."