Philip Hammond has been accused by the SNP of a "scandalous attack on aspiration" as he was warned increasing National Insurance contributions (NICs) for the self-employed would come back to haunt him.

The Government has been accused of breaking an election manifesto promise not to raise NICs as Mr Hammond announced self-employed workers will see contributions increase by 1% to 10% from April next year and a further 1% the year after.

The SNP's economic spokesman, Stewart Hosie, said the changes would discourage people from starting their own business.

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He said: "One of the reasons the Government can't fund its policies is because of the issue with tax yield and I know, I believe in tax competition, but we look at the corporation tax yield, it flatlines, it falls and it definitely falls in real terms for the last four years of the forecast period.

"In order to make amends today or to make the numbers stack up we have seen a scandalous attack on aspiration, on the self-employed, taxing them more, changes to NICs, £4.2 billion or so from people.

"The party of aspiration taxing those who are self-employed putting in active, real, hard disincentives to starting businesses, to employing people, to stepping out on one's own.

"I think that is a decision which will come back to haunt this Chancellor."

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The Government has insisted the shake-up is necessary to make the amount paid in NICs by employed and self-employed workers fairer.

Mr Hammond said higher paid self-employed workers will face increases of around 60p a week in NICs, raising an extra £145 million a year for the Exchequer by 2021-22.

Mr Hosie said the changes would cause would-be entrepreneurs to "take a second look" before pulling the trigger on a new business.

"None of these people will now do this automatically," he said.

"They will take a second look, they will have a pause. They will wonder if the risk is worth it because of the disincentive put in place today."

Former shadow work and pensions secretary Rachel Reeves also attacked the changes.

The Labour MP for Leeds West said: "My back of the envelope calculations suggest that a self-employed person on £20,000 a year will end up paying £20 extra a month because of these changes in National Insurance.

"But also, in the Budget documents we know, and from previous announcements in Budgets, we know that the cuts to corporation tax are worth £3.8 billion, and primarily benefit the largest businesses.

"And yet in this Budget we are increasing taxes on the self-employed by £2 billion.

"It seems to me this is the wrong priority - we should be doing more to help the self employed and small businesses, and less to help the big businesses who are already making large profits."

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However, Conservative Charlie Elphicke (Dover) backed the move by Mr Hammond.

"I heard the remarks from the Leader of the Opposition and the SNP saying isn't it appalling, but actually there should be a level playing field, surely, for the self-employed and for the employed," he said.

"That's something about which I feel quite strongly and I think the Chancellor was right to bring in measures."

Labour MP Stella Creasy (Walthamstow) replied: "What is he going to say to the 10,000 self-employed people in my constituency and the 3,500 self-employed people in his constituency who read the Conservative manifesto, and the four times it pledged that there would no increases in National Insurance?"

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Mr Elphicke said it was a matter of pragmatism and fairness, adding: "It's a matter where the playing field has skewed so much that social justice, fairness and the right thing to do must come first."

Shadow Treasury minister Jonathan Reynolds also criticised the move, saying: "Holiday pay, sick pay, auto enrolment, parental leave, self-employed people do not have equal access to these in-work benefits.

"How then can it be right to put up the tax on them?"

Tory former minister Andrew Murrison (South West Wiltshire) said he has some "concerns" around the National Insurance rise.

He said: "It's very important to ensure that we don't disadvantage self-employed people.

"This party on this side always has been, I hope always will be, the party that supports white van man and, may I say on this particular day (International Women's Day) also white van woman."

He added: "I hope very much we can have some reassurance from the Treasury frontbench later on that plumbers and electricians and plasterers and people of that sort are not going to be disadvantaged."

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Conservative Jacob Rees-Mogg (North East Somerset) sounded a note of caution over the changes to NICs, noting part of the reason for low unemployment since 2008 is due to the "great flexibility" in the labour market.

He added this is something self-employment contributes to.

Mr Rees-Mogg said: "Though I very much doubt increasing (self-employed) National Insurance contributions by 1% and subsequently by 2% is going to change this balance fundamentally, often things economically happen at the margins rather than being an easily identifiable inflection point when you are starting out.

"So I'd be very cautious about this change and would actually urge the Government to look at the whole question between National Insurance and income tax in the round because National Insurance is £130 billion of revenue.

Read more: Chancellor announces £350m funding boost for Scotland

"It's an enormously important source of funding for what the Government wishes to do but its relationship to income tax is one that creates confusion and distortions within the system, and this is just one of those distortions.

"I'm not sure making a minor change at the edges is the right way to go about changing the relationship of taxation between the self-employed and the ordinarily employed."