Owners of 300,000 Rover and MG cars sold within the past three years were on Sunday facing uncertainty over the honouring of their new-car warranties as administrator PwC began examining options for the company's future.

Dealers said the manufacturer's warranties should hold good while MG Rover and its sister company Powertrain, which makes engines, remain in administration. However, should PwC decide to put MG Rover formally into receivership, such owners would find themselves subject to the goodwill of the 350-strong franchised dealer network that supplied their cars.