Cab company Addison Lee has pledged it will operate only electric vehicles from 2023.
The London firm said it is investing £160 million to shift its 4,000-strong fleet to electric.
This will involve putting 200 Volkswagen ID.4 vehicles on the capital’s roads every month from November.
The commitment is the largest single order of electric vehicles made by the UK’s private hire industry, according to Addison Lee.
The firm’s chief executive Liam Griffin said: “As the transport provider of choice for many businesses and passengers, we know that we play a critical role in London’s transport network.
“Over the years, we have invested in our vehicles and technology to ensure we do all we can to make London a greener place.
“We are now going even further, by partnering with Volkswagen to invest in a rapid transition to electric.
“In doing so, we can help more businesses reduce their carbon footprint and give passengers greater access to green, safe and premium transport options as life gets back to normal.”
Transport Secretary Grant Shapps said: “As we continue working tirelessly to decarbonise our transport network, I am thrilled to see Addison Lee lead the way through pledging to electrify their fleet by 2023.
“This Government has committed to reach net zero by 2050. With more than 500,000 electric vehicles now on our roads and nearly 25,000 public charge points, we’re at the beginning of an electric vehicle revolution which will help create communities free from pollution as well as supporting thousands of jobs in the supply chain over the coming decades.”
Another private hire firm, Uber is aiming for all its cars in London to be fully electric by 2025.