Transport bosses will need three more weekend closures to complete their restoration project at the Blackwall Tunnel.

The project is due to be completed by December this year – several months ahead of the date originally predicted.

The final closures are needed for upgrade works on the 1.4km tunnel that cannot be completed when traffic is flowing through.

It will shut southbound on the Easter Bank Holiday weekend and the weekends of June 10-13 and August 12-15.

Garrett Emmerson, Chief Operating Officer for London Streets for TfL, said: “Although these works are progressing even better than we had hoped, there will be additional congestion due to these weekend closures.

“We therefore ask people to plan their journeys for these weekends in advance and avoid travelling through the area if at all possible.”

During the weekend closures, the Rotherhithe Tunnel will again operate two lanes in the southbound direction only, while the Blackwall Tunnel will carry only northbound traffic. Drivers will also be able to use alternative river crossings such as Tower Bridge, the Woolwich Ferry or the Dartford Crossing to complete their journey.

Work costing �70 million started in February 2010 and saw a series of weekend closures last year.

New ventilation shafts are now installed in the tunnel’s four shafts, with upgraded CCTV and new communications systems throughout.

There are now 26 inlets in the tunnel wall, fitted with emergency phones and a fire extinguisher for any vehicles that have broken down.