The government has launched a public consultation into proposals to spin out part of English Heritage into a new charity arm and said it would provide a further £5m of funding to aid the process.
The new charity will keep the name English Heritage and will become independent in 2015, the proposals say. It will be given an eight-year licence to manage the National Heritage Collection, which includes Stonehenge, Hadrian’s Wall and about 420 other historic sites, monuments and collections.
It is expected to have a turnover of £90m, which would make it the 65th largest charity in England and Wales.
The arm of the organisation responsible for planning and heritage protection will stay within government and will be known as Historic England.
The government previously announced a one-off £80m grant to aid the transition, when it announced the initial plans in the summer.
This funding, together with £83m to be raised from third parties, will allow the charity to "undertake a huge programme of conservation for properties and works to improve the visitor experience", a statement from the Department for Culture, Media and Sport said.
The charity will also receive grants to cover a £20m shortfall between the cost of maintaining the national collection and the income received from visits. This will decline year-on-year, and the charity has been set a target of being self-sustaining by 2023.
The DCMS said on Friday that it would provide a further £5m to cover the costs of setting up the two new organisations.
Maria Miller, the culture secretary, said: "The incredible buildings and places up and down our country are admired across the world, and these proposals – along with government’s huge investment – will enable English Heritage to look after and protect them for generations to come."
Loyd Grossman, chairman of the Heritage Alliance, a group of 90 heritage charities including the National Trust, said that a reassessment of the government’s role in securing our heritage was "very timely", and that his organisation would seek to use the consultation to "secure the best possible outcome for our historic environment".
The consultation will be open until 7 February.