The curved wall which surrounds the eastern end of Constitution Hill and Spur Road in front of Buckingham Palace was designed by the architect Sir Aston Webb and the sculptor Thomas Brock to celebrate the reign of Queen Victoria in 1901.
The scheme includes the Queen Victoria Memorial monument, the Memorial Gardens, and the Dominion gates which represent Canada, South Africa, West Africa, Australia, Newfoundland and the Malay states.
Connecting the gates is a curved retaining wall made of Portland stone, and is formed of large stone plinths at the top and base, with stone balusters between the two plinths.
As part of strengthening works, a stainless steel skeleton structure will be inserted into the curved wall, which flanks the grand processional route The Mall.
In addition, repairs will be carried out and the stone will be cleaned by specialists from Stonewest, which has previously worked on other historic landmarks such as St Paul's Cathedral and Lambeth and Chiswick Bridges.
The works will take place in two phases. The first phase will be on the St James's Park section of the wall which started this month and is expected to be completed in mid November 2016. The second phase will involve the Green Park section and take place from August to November 2017.
The Green and St James's Parks manager Mark Wasilewski said: "The Royal Parks prides itself on being home to some of the most iconic statues and monuments in London from the Queen Victoria Memorial and the 18ft Achilles Statue to the Albert Memorial and the Peter Pan Statue, all of which have their own unique stories and provide a snapshot of the parks' long history.
"But managing them comes at a cost; with 140 monuments across the eight royal parks maintaining them runs into millions of pounds, and the repairs to the Grade 1 listed wall outside Buckingham Palace is the latest restoration project to ensure this iconic feature can continue to be enjoyed by millions of visitors each year."
While some areas around the wall have been fenced off for safety reasons, the impact of the works on visitors will be minimal.