An Uber advertising campaign in London has claimed that its car-pooling service reduces traffic, contradicting the findings of the US ride-hailing app company’s own research.

A large billboard poster displayed in London this month said: “Uber Pool reduces traffic by moving more people in fewer cars”.

It was displayed at a busy junction near two of Transport for London’s main offices in Southwark. The poster has since been replaced.

The claim contradicts evidence from a study sponsored by Uber and fellow ride-hailing app company Lyft that showed both were together responsible for as much as 13% of miles travelled by vehicles in the centre of San Francisco, one of six US cities studied. The report by the transportation consultancy Fehr & Peers was based on data from Uber and Lyft.

In a blogpost accompanying the research Chris Pangilinan, Uber’s head of global policy for public transportation, acknowledged that the evidence showed that his company and Lyft were likely to be contributing to an increase in congestion.

The effect of ride-hailing apps on congestion is contested. They could reduce traffic by encouraging people leave their cars at home, or they could increase the number of vehicles on the road if people switch from public transport.

Uber faces a TfL decision on 25 September as to whether its London operating licence will be renewed. Last year the company won a temporary legal reprieve on a ban by saying it had changed its policies on driver background checks and crime reporting.

Last month Uber said it had 100 million monthly active users in 65 countries, and that its car-pooling service, which allows multiple separate users to share the same vehicle, had saved 1.7m driving miles in the UK capital this year.

The company has been unable to provide the methodology for the claim made in the London ad, or to provide evidence of any assessment that took into account the overall effect of the pooling service on traffic.

Asked about the poster, an Uber spokeswoman said: “We often run marketing campaigns all over the world to showcase the many features and products available through the Uber app, whether that’s our safety toolkit or Uber Pool. More than 350,000 people in London regularly use Uber Pool to share their journey, and in 2019 shared journeys have saved over 1.7m miles from being driven in London.”

Ride-hailing businesses have repeatedly said they aim to reduce congestion on roads, but the inexorable rise of traffic has led Uber and others to look at different solutions. Uber’s Jump, Bird and Lime are among a number of startups that are launching, or have launched, electric scooters and bikes in US and European cities.

Uber, Airbus and the German firm Lilium are among the companies hoping that light aircraft capable of vertical takeoff and landing will offer a different solution to congestion.