Prime Minister David Cameron said the move would make the Scottish Parliament "one of the most powerful devolved parliaments in the world".
But Scotland's First Minister Nicola Sturgeon of the Scottish National Party (SNP), who was holding talks with Cameron in Edinburgh later on Thursday, said earlier that the proposals do not go far enough.
The proposals include new powers to set the rates and thresholds for income tax and also would see the Scottish government receive a larger proportion of tax revenues.
"The draft clauses published in this document are the next stage in delivering that commitment," the bill said.
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"Our United Kingdom is a success story. And Scotland has played a crucial part in that and will continue to do so," it added.
The process to make them law will only begin after Britain's general election on May 7 which could see dramatic changes in which parties hold Scottish seats in the British parliament in London.
This could cast the party as power brokers if, as polls suggest, Cameron's Conservatives or the main opposition Labour party fail to win an outright majority.
The nationalists have indicated they could team up with Labour but would use their position to push for more powers for the Scottish Parliament which go beyond the current proposals.