A major upgrade to the A47 is on track, the government has insisted, despite documents which show it is one of a raft of road schemes promised before the election under review.

https://infogr.am/a47-9969163710504

Highways England – the taxpayer-funded company in charge of dualling three stretches of the road and carrying out other upgrades – has said the pressure to work quickly had put a strain on budgets, in board minutes obtained by the Labour Party.

But the Department for Transport insists that it is not unusual to review projects.

The £300m programme to upgrade the A47 was announced in the run up to last year's general election.

The plans include:

• A47 dualling from North Tuddenham to Easton;

• A47 dualling from Blofield to North Burlingham;

• A47/A12 Great Yarmouth junction improvements, including reconstruction of the Vauxhall roundabout;

• A47/A11 Thickthorn junction improvement to the interchange to give improved access to Norwich;

• A47 Guyhirn: a new larger junction linking the A47 with the A141 in Cambridgeshire;

• A47 Wansford to Sutton: dualling the A47 between the A1 and Peterborough.

Highways England has previously said it would hold a public consultation on the options for the route by the end of this year with its plans set to be unveiled next year, but work is not due to start until 2020 and may not be completed until 2023.

The transport body has already come under fire from MPs over the length of time it will take to start the construction, and the prime minister promised improvements on the A47 would begin by 2020, even if he had to 'get the diggers out' himself during a visit last year. Shadow transport secretary Lillian Greenwood said: 'I know that the slow pace of improvements to the A47 is already a cause of huge frustration, so the news that the project has been placed under review is deeply concerning.'

Drivers already face a wait until 2023 and there are now real fears that the deadline could slip further. George Osborne promised to 'transform' the A47 before the election and ministers need to make sure that the pledge is honoured.'

North-West Norfolk MP Sir Henry Bellingham said that given the earlier setbacks in bringing forward the A47 schemes, further delays would be unacceptable. 'I already have a meeting with the transport secretary Patrick McLoughlin to discuss rail issues so I'll be adding this to our agenda,' he added.

A DfT spokesman said: 'Highways England is on track to deliver a major £15bn roads investment programme on time and on budget.

'This includes the vital A47 corridor which is to benefit from £300m of investment. This is the largest upgrade to our roads in a generation that will bring benefits to people up and down the country. It is entirely reasonable on a project of this scale for us to regularly review progress.

'There have been no cost overruns on the current schemes in the Road Investment Strategy and the work Highways England is delivering continues apace.'

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