Tourists will completely bypass Sidmouth if a long-awaited ‘superhighway to the South West’ goes ahead as planned.

That is the warning from town councillor John Dyson, who drew up his own plans for improvements to the A303 – not knowing that the Government would announce the £2billion upgrade on the very same day.

Highways bosses are calling for the road to become a dual carriageway between London and Ilminster and then widening the A358 to the M5 at Taunton.

Councillor Dyson fears this will mean tourists bypass the whole of East Devon – but said his idea of a route through the Blackdown Hills has faced little opposition.

Speaking at the town council meeting on Monday, he said: “East Devon is going to be that bit less accessible – the road will bypass it completely.

“It won’t affect us in my time but in 10 or 20 years it will have a negative effect on all the coastal resorts in this area.

“We need to be more proactive as a town – I’m doing what I can to help businesses and the hospitality trade in the future.”

The Blackdown Hills Area of Outstanding Natural Beauty (AONB) near Honiton had long been a ‘sticking point’ but the new proposals bypass it and take commuters to the motorway via the A358 when the A303 splits at Ilminster.

The A303 will also go under Stonehenge, another heritage site and traffic blackspot, with plans for a 1.8-mile tunnel.

Cllr Dyson said the move will cut travel times between Cornwall and London, but if tourists do not have to stop en route, then East Devon’s resorts may lose out.

He submitted proposals several months ago for an alternative, straighter route from Ilminster to Honiton to alleviate traffic and cut travel times.

He said it would have little impact on the Blackdown Hills and had received ‘broad support’ from AONB representatives and Honiton Town Council.

And while it has not been written off, it is unlikely to receive attention from the Highways Agency until the Government’s development is completed.

Cllr Simon Pollentine said: “These things are going to happen – we have to make the most of them.

“It’s vital for our tourism that people get into East Devon.”