Transport for London (TfL) has announced two weekend closures of the southbound Blackwall Tunnel, which are required to support the opening of the new Silvertown Tunnel.

The closures, which will take place across the weekends of Saturday, July 20 to Monday, July 22, and Saturday, August 17 to Monday, August 19, will allow for the final road configuration to be implemented, as well as road resurfacing and safety barrier works to be carried out.

These dates have been chosen to avoid key events happening in London during the summer.

Plans for the Silvertown Tunnel, first developed in 2012, aim to reduce traffic congestion and deliver faster, more reliable journeys in London when it opens in 2025.

Expected to cut travel times by up to 20 minutes, the new tunnel will also bring a significant increase in bus services across the river and propose a new cycle shuttle service for cyclists.

There will also be a increase in bus services across the river and a proposed new cycle shuttle service through the tunnel for cyclists.

To avoid clashing with key London summer events, specific dates have been chosen for the related traffic management, according to TfL.

Weekend closures of the Blackwall Tunnel for southbound traffic will begin at 12.01am on Saturdays, with normal traffic flow restored by 5amam on Mondays.

Northbound traffic will remain unaffected as it will be diverted through the southbound Blackwall Tunnel when needed.

Drivers are advised to plan their routes in advance, checking before they travel so they can consider any other potential traffic impacts or restrictions, such as the height and weight limits at Rotherhithe Tunnel and Tower Bridge, both of which are outside the Congestion Charge zone.

Roads and alternative river crossings in east and central London are expected to be extremely busy with traffic around Rotherhithe Tunnel and along the A13 Commercial Road between Canning Town and Whitechapel heavier than normal over the weekends due to the closures.

The Woolwich Ferry, which now departs every fifteen minutes, seven days a week, will be in operation across the weekends.

The route 108, the only bus route that operates through the Blackwall Tunnel, will be split in two, operating between both Lewisham and North Greenwich and between Canning Town and Stratford.

HGV drivers and those with vans over two meters in height or weighing more than two tonnes should consider avoiding central London.

To keep drivers informed, additional variable messaging signs will be placed on main roads approaching the Blackwall Tunnel.

TfL has also collaborated with third-party app providers, such as Waze, to alert regular Blackwall Tunnel users to the southbound closures.

Nick Fairholme, Director of Capital Delivery – Systems at TfL, said: “We are now in the final phase of works to complete the Silvertown Tunnel and these closures will help us to to start to get the tunnel ready to open.

"We appreciate that these planned weekend works will have an impact on some drivers and are doing everything we can to limit potential disruption - including ensuring a northbound route through the Blackwall Tunnel is maintained throughout.”