Car dealership group Pendragon has said it will slash 1,800 jobs and shut 15 of its showrooms.
The Evans Halshaw and Stratstone owner said it expects around 400 redundancies as a result of closing its loss-making sites, with a further 1,400 job cuts coming as part of plans to make its operations "leaner and more sustainable".
The cuts come as part of a review started by the firm before the coronavirus crisis hit, which further damaged demand for cars.
Bill Berman, Pendragon chief executive, said: "These have been difficult decisions for the board to make and our priority now is to manage the transition to our new operating model.
"The Covid-19 pandemic is a uniquely challenging situation and we want to protect as many jobs as we can sustainably and the proposed redundancies are, of course, extremely regrettable.
"The actions that we are undertaking are for the long-term health and success of the group and ensure that we emerge from the pandemic as a more competitive and stronger business with the ability to thrive in the future."
The news comes as figures showed the number of cars built in the UK over the past six months has slumped to the lowest since 1954.
The Society of Motor Manufacturers and Traders estimated that 11,349 jobs were axed in the past six months at carmakers and companies that supply them with parts and services.
SMMT chief executive Mike Hawes said: "These figures are yet more grim reading for the industry and its workforce, and reveal the difficulties all automotive businesses face as they try to restart while tackling sectoral challenges like no other.
"Recovery is difficult for all companies, but automotive is unique in facing immense technological shifts, business uncertainty and a fundamental change to trading conditions while dealing with coronavirus.
"Our factories were once set to make two million cars in 2020 but could now produce less than half that number, a result of the devastating effects of the pandemic on top of already challenging market conditions and years of Brexit uncertainty."
Hawes said the long term future of the motor industry now depended on securing a good trade deal, pointing out that the EU remained the biggest market for UK cars.
Unite assistant general secretary Steve Turner said: "Buffeted by the twin forces of the coronavirus pandemic and the ongoing challenges Brexit poses to the sector, the future of the UK's world-leading automotive sector and the thousands of well-paid and skilled jobs that come with it, is in doubt.
"These historic lows in production show the industry is standing at a crossroads: Either the Government leaves it to become a shadow of its former self or provides the support and investment needed for it flourish as a producer of the next generation of cleaner cars.
"UK vehicle manufacturers have a vital role to play in the country's, and indeed the world's, transition to low carbon, but they cannot do this until the Government lays the groundwork."
