Labour has denied that the government’s plans for the Lower Thames Crossing will be scrapped if successful at the polls on Thursday.

Speaking last week, shadow transport secretary Andy McDonald said “all options” would be considered again if Labour wins, including the prospect of another crossing at Dartford or one further east.

He said: “Before we agree to spending £6.5bn we have to be sure that we will actually resolve the problem of congestion around the existing crossing and that is then done in a way that does as little damage as possible.”

But after backlash from both Tory parliamentary candidate Gareth Johnson and his Labour opponent Dr Bachchu Kaini, the party were forced into a U-turn on Friday.

“There is a clear need for a new Lower Thames Crossing and it should proceed as quickly as possible,” said a national Labour spokesman.

“We do not intend to halt the process but, as with any incoming government, we would need to ensure that the decision making process has been completely robust and represents the best value for money.

“The £6.5bn project needs to be a good use of taxpayers’ money. It also needs to work for local people and address their concerns.”

In April the government said the crossing — a multi-billion pound bored tunnel — would create a new link between the A2 and the M25 and reduce the burden on the Dartford Crossing.

The planned route would run from the M25 near North Ockendon, cross the A13 at Orsett before crossing under the Thames east of Tilbury and Gravesend, with a new link road taking traffic to the A2 near Shorne, close to where the route becomes the M2.

Another £10m was promised to help Dartford’s roads in the meantime.

Mr Johnson, who has served as Dartford’s MP since 2010, said going back on the plans would be “a disaster” and that another crossing next to the existing one would be “catastrophic” for the town.

The issue is one of few to have united the Conservatives and Labour in Dartford in recent times, with both parties having backed the government’s decision.

The borough’s Labour leader, Cllr Jonathon Hawkes, also condemned the “further delay and uncertainty” that would be caused by re-opening the crossing debate.

Speaking after the U-turn, he said: “We’ve always been clear that Option C is only way forward to getting Dartford moving again and reducing the air pollution that has afflicted our town for too long.

“The government now need to get on with the job and start work on the new crossing. We strongly made that case this week and we are pleased that it’s clear that Labour’s priority is to proceed with the big infrastructure projects that are vital to the future of our area.”

Dr Kaini added: “As MP for Dartford I will always put Dartford first and I have done this week.

“We need to get this project started as soon as possible and ensure the crossing on time and on budget and delivers the outcomes to people in Dartford that the government has promised.”