The National Trust for Scotland chief executive says it is "almost inevitable" it will merge with the government body for historic buildings

The chief executive of Scotland’s biggest conservation charity has said he believes it is almost inevitable it will merge with a similar government body.

The National Trust for Scotland (NTS) uses its £53 million a year income to look after 190,000 acres of Scottish countryside, including 46 munroes, as well as 10,000 archaelogcial sites, 35 major gardens, 130 historic buildings and Britain’s only dual World Heritage Site, St Kilda.

Since it was formed in 1931, NTS has been entirely independent of the government and has been run by a voluntary board elected from its 330,000 members.

However, recent years have seen the trust struggle to modernise and make enough money to cover its costs. In 2009, it was forced to sell its prestigious Edinburgh Charlotte Square headquarters and 2010 saw a major governance review recommend a series of reforms.

Now, its chief executive Simon Skinner, who was appointed in 2015 with a reform agenda, has admitted the charity “occupies the same space” as Historic Environment Scotland (HES), the non-governmental body formerly known as Historic Scotland.

Skinner said the bodies have a “shared agenda” and referring to a possible merger, said: “Over time, it is almost inevitable. The same space is being occupied and we need to look at that."

He added: “I think elements of it could come together. I don’t see why you wouldn’t. If you go to an industry analogy, you have back offices we both run, payroll systems, we have conservators, they have conservators.”

HES looks after 300 monuments and buildings in Scotland, including Edinburgh Castle and Stirling Castle. Its has charitable status but its management board is appointed by the Scottish Government and last year it received £36m grant income, while also generating £17.6m in earned income.

As well as conservation work, HES carries out stautory duties for the government in relation to listed buildings, planning and development support, and World Heritage Sites.

A spokesman said there are no plans to merge the two bodies.

He said: “We have a strong working relationship with colleagues at the National Trust for Scotland on a wide range of matters, such as the current Jacobites campaign and helping to manage and highlight world heritage sites such as St Kilda.

“However, there are no proposals to change the nature of that relationship.”