The Prime Minister will give his backing to the A303 tunnel plan in a visit to Stonehenge tomorrow.

He will visit the ancient monument to confirm the government's plans to tunnel beneath the ancient monument, as revealed by the Salisbury Journal three weeks ago. His visit will follow that by the Deputy Prime Minister Nick Clegg in the morning.

The announcement had been planned as addition to the Chancellor of the Exchequer George Osborne's Autumn Statement on Wednesday - which was exclusively previewed by the Salisbury Journal three weeks ago.

However, in a move that appeared to jump the gun, English Heritage confirmed the government's intentions in a statement on their website tonight (Sunday). The statement was later removed from the website but it said:

"Today Monday 1 December, (2014) the Government announced in its Autumn Statement that it will be investing options to remove the A303 from the Stonehenge landscape. 

"English Heritage and National Trust, as guardians of Stonehenge and its World Heritage Site, see this announcement as a 'truly momentous decision' in the modern history of one of the most famous places in the world."

Helen Ghosh, Director General of the National Trust, said: “The importance of this announcement today cannot be overstated. After many false starts and challenges, this does for the first time feel like a real opportunity to tackle the blight of the road that dominates the landscape of Stonehenge.  

“If designed well, putting the A303 into a tunnel will bring the Stonehenge landscape together once more, creating space for nature and improving the site’s tranquillity. I know there will be some sadness that people will no longer be able to see the stones from the road, but visitors will once again be able to hear the sounds of skylarks singing rather than the constant noise of traffic.  

“We’re committed to finding alternative ways for even more people to see the Stones on their journey and for future generations to experience and explore this inspiring prehistoric landscape as our ancestors did.”  

Dr Simon Thurley, Chief Executive of English Heritage, said: “This will be the biggest single investment ever by Government in this country’s heritage and is truly a momentous decision.  

“We felt so proud to close the A344 last year and build award-winning visitor facilities at Stonehenge. We have been campaigning for a tunnel to remove the blight that is the A303, for the past 30 years. This news is the icing on the cake and vindicates all  our hard work.  

“We have been trying to find a solution for the A303 improvements since 1986 when Stonehenge became a World Heritage Site; recognition that it is one of the best known and most important prehistoric landscapes in the world.  

“It is vital that any new scheme to put the A303 into a bored tunnel is located in the right place and designed to the best specification.    

“This is about investing in the future. We have a responsibility to future generations to get this right as we provide a world class solution for a world class place.”