Bob Lutz, GM's vice chairman who had planned to retire later this year, is to stay with the restructured manufacturer and lead its brand rebuild.

Lutz will head the US carmaker's marketing and PR machine, while still overseeing product design.

He said Cadillac will be General Motors' main weapon against rival European luxury marques such as Jaguar, BMW and Mercedes Benz, while the Buick brand will be pitted against Lexus in the upscale North American car market.

Lutz, 77, said in a webchat that GM's remaining four brands would be given more recognisable identities as part of an overhaul of marketing and advertising strategy.