Labour will put forward amendments to the next Scottish budget to avoid cutting public spending which will include raising income tax rates, Scottish Labour leader Kezia Dugdale will say.

Dugdale will commit her party's MSPs to drafting and voting for amendments which aim to raise the basic rate of income tax by 1p in the pound and the top rate to 50p.

From April 2017 the Scottish Parliament will be entirely responsible for setting the rates of income tax workers in Scotland pay.

Labour's manifesto in May's election included proposals to raise the income tax levels to protect levels of public spending.

The party came third in the election behind the Conservatives and the SNP who both want income tax rates to remain unchanged following further devolution to Holyrood.

In her speech to conference delegates in Liverpool on Monday, Dugdale will say: "With the full range of powers the Scottish Parliament now has, the SNP Government faces a clear choice.

"Accept a Tory Budget from Westminster, or go our own way with proposals to grow the Scottish economy and protect our schools and hospitals."

She will add: "If the SNP minority Government do not accept these proposals, and try to force another austerity budget through Holyrood, we will vote against it.

"If they want support, they'll need to look to the Tories for that. Labour will not help the SNP pass an austerity budget."

The Scottish Labour leader is expected to single out criticism towards the First Minister in her conference address.

Dugdale will say: "Nicola Sturgeon is the most powerful First Minister that Scotland has ever had.

"In her hands, she has more power than any of her predecessors to change our nation.

"But for a woman who is famous for saying yes, her answer when you ask her to use the powers she has is always no.

"In contrast Labour will not "sit back and do nothing".

A spokeswoman for the Scottish Government defended not raising income tax rates to combat austerity.

She said: "The First Minister has been clear that hard working families should not have to pay the price of UK Government austerity.

"Where we have the powers to do so, we are making taxation fairer and more proportionate to the ability to pay, while also raising additional revenue.

"Our income tax proposals for 2017/18 and beyond will protect lower income taxpayers - but also generate extra revenue of around £1.2bn by 2021/22 to invest in key public services.

"Similarly, we are proposing progressive reforms to local taxation which will, over the lifetime of this Parliament, raise an additional £500m to invest in raising educational attainment."