In June 2014, the minicab company shifted its PR duties from Ogilvy PR to W Communications, following increasing competition from the likes of Hailo and Uber.
However, W stopped working with Addison Lee nearly two years ago when PR budgets were reduced and there was a focus in the business to build the company's brand and technology strategy, W Communications founder Warren Johnson said.
Despite this, the agency has been sent the RFP, and an Addison Lee spokesperson told PRWeek that W would be responding to it.
It is unclear which other agencies have been sent the RFP.
Its public affairs account, which is currently held by WPP agency Burson-Marsteller, is not affected and there are no plans to look for a new agency for the public affairs brief, the spokeperson said.
Addison Lee was founded by John Griffin in 2002 and was sold to US-based equity firm The Carlyle Group in 2013 for an estimated £300m. It operates a fleet of almost 5,000 taxis in central London and has an estimated annual revenue of £232m