Ministers have given the go-ahead to the £10bn Lower Thames Crossing road tunnel, one of the most expensive infrastructure projects in UK history.

Transport Secretary Heidi Alexander approved the development consent order (DCO) for the scheme on Tuesday.

It will be funded primarily by the private sector, according to the Financial Times, confirming speculation after hints from Chancellor Rachel Reeves in a speech earlier this year.

Plans for the Lower Thames Crossing involve the construction of a 14-mile road and tunnel, the largest in the UK, to the east of London and running under the River Thames.

The project aims to alleviate pressure off the highly congested Dartford Tunnel. One official told the FT it would be a “key strategic route” for drivers, freight and logistics moving between southern England and the Midlands.

“This demonstrates this government’s commitment to delivering the vital infrastructure the country needs,” they added.

While the plan has the backing of some local politicians and business groups, it faced criticism last year after revelations its planning application had reached more than 350,000 pages, nearly 250 times longer than War and Peace.

Costs have risen from around £6bn to nearly £10bn since the scheme was first put together in 2018. Construction is expected to start in 2026 or early 2027.