A consensus on giving more powers to Scotland if it rejects independence could be achieved soon after the 2015 general election, according to the Prime Minister.

All of the major UK political parties have now presented their devolution proposals following the publication of the Conservative Strathclyde Commission on the Future Governance of Scotland.

The Tories want to give Holyrood full control over income tax, the commission said, an advance on Labour's proposal to devolve three-quarters of the basic rate and closer to the Liberal Democrats' proposal to devolve almost all income tax powers.

Prime Minister David Cameron said he wants his party's proposals implemented soon after the 2015 general election, but recognised the need to build consensus.

Scottish Conservative leader Ruth Davidson said the Commission was aware of the the other parties' devo proposals, but insisted it "is not a bidding war or a Dutch auction".

Scottish National Party deputy leader Nicola Sturgeon urged Scots to shun the "desperate bidding war from the unionist parties" and vote Yes.

Fellow nationalist Patrick Harvie, co-convener of the Scottish Greens, said Scotland risks being forgotten in 2015 if it votes No as the Tories will shift their focus to the in/out referendum on the European Union.

Lib Dem peer Lord Jeremy Purvis, leader of the cross-party Devo Plus group, said all of the major parties are now "clearly and unequivocally supporting a stronger Scotland".

But Devo Plus chairman Ben Thomson said they must a reach a consensus before the referendum, rather than waiting until after the 2015 general election.

The Prime Minister said: "Ruth supports the Commission's key recommendations and wants to see them implemented. I agree with her.

"All the mainstream pro-UK parties believe in further devolution, so whilst we would want to build consensus for a set of measures and legislation, there is no reason why these changes shouldn't happen early in the next Parliament."

Launching the commission's report in Glasgow, Ms Davidson said: "While the commission didn't operate in a vacuum this is not a bidding war or a Dutch auction.

"This was about having practical policies that we could deliver, would benefit the people of Scotland and would stabilise the UK."

She added: "In terms of 'do I think we have got all of the answers?', I don't have a crystal ball. I think this is a very good blueprint for going forward."

The commission recommends that Scottish VAT receipts should be assigned to Holyrood.

The tax-free personal allowance should remain reserved at Westminster, but the Scottish Parliament should decide on rates and bands, it said.

Holyrood should not be prevented from supplementing UK benefits out of its own budgets and should be given more responsibility on some welfare issues, particularly cash benefits such as housing benefit and attendance allowance, it said.

An independent Scottish Fiscal Commission should be created to produce official macro-economic and fiscal forecasts, it added.

Mandatory committees of the Scottish Parliament should be led by opposition members, and members of the Scottish civil service should also serve elsewhere in the UK as part of their career progression, the Commission said.

Opposition parties claim that the SNP has used its majority in Holyrood to limit committee scrutiny and whitewash their reports.

Ms Sturgeon said the Tories have a "long record of broken promises to Scotland" and the only way to guarantee more powers is to vote Yes.

"The debate is no longer about whether Scotland needs more powers - it is now about the extent of those powers, and how we can best guarantee them," she said.

"With their package of proposals today, the Tories have demolished a central pillar of the No campaign by recommending ending uniform tax and benefits across UK.

"They have also, inadvertently, made the case for independence by saying they wanted to recommend devolving VAT but can't under EU law, as Scotland needs to be independent to control VAT and all taxes.

"What we are now seeing is a desperate bidding war from the Unionist parties."

She added: "This is the party that opposed devolution tooth and nail. They broke promises for more powers in the past, and Ruth Davidson was elected leader saying she had drawn 'a line in the sand' against more powers.

"Now they want us to believe they have had a sudden conversion to Scotland's cause."

Mr Harvie said: "The reality is if we say No, we're relying on whoever wins the UK general election in May remembering that Scotland exists.

"Frankly, the focus at Westminster will be the EU referendum, and we would regret seizing the unrivalled opportunity in September to set our own agenda by voting Yes."

Mr Purvis said: "A growing centre of common ground has developed. This means that, in the referendum in September, the choice for people is between voting to stay in the UK but to improve it, or to take the increasing risks and unknowns of independence."

Mr Thomson said: "It would now be helpful in the run-up to the referendum if the three parties set out a consensus position of the minimum powers they would all guarantee to devolve including full income tax powers, housing benefit and attendance allowance.

"This would give the public confidence that significant further devolution giving Holyrood greater accountability would really happen after a No vote."