Buyers of new-build homes could be in line for up to £80,000 of help as part of a Scottish Government scheme hailed as a potentially "game-changing initiative".

Ministers have allocated £220 million over three years for the new Help to Buy (Scotland) shared equity scheme.

From Monday, both first-time buyers and existing homeowners buying a new-build house from a participating builder will be able to get up to 20% of their purchase price.

The Scottish Government then takes out an equity stake in the property, which the buyer has to repay at a later date.

Those buying properties valued at up to £400,000 can get help, but those who already own a house will be expected to sell it before they purchase a new home under the scheme.

It is expected buyers will need a deposit of 5% of the property price, and this and their mortgage must cover at least 80% of the cost of their new home.

Deputy First Minister Nicola Sturgeon said the initiative would help both buyers and the housing industry, which has been struggling in recent years.

"There is no doubt that getting on to, or moving up, the property ladder has become tougher in recent years," she said.

"House buyers are being hampered by the lack of affordable mortgages, with high deposits often a major barrier.

"The Help to Buy (Scotland) scheme will not only help people to buy their first home, it will also help 'second-steppers' and others move to a new property.

"The scheme will also help support the housing industry alongside our commitment to investment in affordable housing across Scotland."

Philip Hogg, chief executive of the house-building industry body Homes for Scotland, said a similar scheme in England had generated more than 12,500 sales since being brought in in April.

He said that given the "immediate and significant impact" it had, it was "absolutely imperative that comparable levels of support were provided here to ensure that buyers, builders and the wider Scottish economy were not disadvantaged".

He added that the Scottish Government had now acted in a "pragmatic way to encourage the building of more homes and support vital jobs, skills and apprenticeships".

Mr Hogg said: "Increasing the range of options available to purchasers, we believe Help to Buy (Scotland) could be a game-changing initiative, acting as the required catalyst to help reverse the downward trend we have witnessed in home building over the last five years."

More than 30 housebuilding firms are participating in the scheme north of the border, including well-known companies such as Miller, Cala and Persimmon.

Both Homes for Scotland and the Council of Mortgage Lenders (CML) will be involved in a new group to monitor its progress, with Paul Smee, CML director-general, saying it "fully supports" the shared equity initiative.

Mr Smee said: "Lending to Scottish borrowers reached its highest level since 2008 in the second quarter of this year, and with schemes like Help to Buy, conditions are improving for home-buyers."

Buyers will not be eligible for help under the scheme if they can reasonably afford more than 90% of the full purchase price of the property.

Those who get help will be required to take out a repayment mortgage with a qualifying lender.

Andy Gray, managing director of mortgages at Barclays, said: "We are happy to announce that Barclays is joining the Help to Buy (Scotland) equity loan scheme.

"This is good news for Scottish borrowers who are looking to buy their first home or move up the housing ladder.

"Barclays is very happy to be supporting the Scottish housing market and look forward to helping customers purchase a new-build property through this scheme"

Tracie Pearce, head of group mortgages at Nationwide, said it will also be accepting Help to Buy applications "as we are keen to support the Scottish Government's efforts in helping the mortgage market to move forward".