The government has approved plans to purchase one of the world's largest tunnelling machines for the Lower Thames Crossing, marking significant progress on the major infrastructure project.

Following the Chancellor's recent commitment of £891 million in funding, the project's tunnelling partner is now seeking suppliers to build the enormous boring machine. The 16.4-metre-wide machine will create the UK's longest road tunnel, stretching over 4 kilometres beneath the Thames. 

The crossing will double road capacity east of London, featuring three lanes in each direction and connecting Kent and Essex. Work is set to begin next year, with the tunnelling machine expected to start digging in 2028.

Roads and Buses Minister Simon Lightwood said: "The launch of the procurement process for Europe's largest tunnelling machine marks a major step forward for this transformational project, backed by £891 million in the Budget which demonstrates this Government's determination to deliver the infrastructure our economy needs to grow."

The project aims to be Britain's greenest road and the first major infrastructure scheme to achieve carbon-neutral construction. It will create two new public parks using excavated material and establish six times more green space than actual road surface.

Matt Palmer, Executive Director of the Lower Thames Crossing said: "The search for our giant tunnel boring machine is now on, putting us on track to open the Lower Thames Crossing in the early 2030s."

The crossing is expected to open in the early 2030s, easing congestion at Dartford.