Shell and Murray's Project M could spawn a regular-production model.

Oil giant Shell has announced that it has teamed up with former McLaren designer Gordon Murray to develop an experimental city car for the world's most crowded urban centers.

Temporarily called Project M, the tiny three-seater is an update of the T.25 concept (pictured) that Gordon revealed in 2010. To save as much weight as possible, the Project M will use the engineer's patented iStream manufacturing process which bonds lightweight composite body panels directly onto a sturdy steel frame.

Project M's dimensions were not given, but the car is expected to be even smaller than the Lilliputian smart fortwo. It will offer space for up to three passengers in a triangular 1+2 configuration, a setup loosely inspired by the McLaren F1 that Murray penned in the 1990s.

Shell promises the Project M will be able to return up to 100 mpg in a mixed cycle thanks to a tiny gasoline-powered engine mounted over the rear axle, but additional technical details have not been provided. The engine is being designed from scratch by Osamu Goto, an engineer whose resume includes designing numerous Formula One engines for Honda in the 1980s.

Shell, Murray and Goto are expected to introduce Project M next November. The car is being built as a simple design study, but Shell has hinted that it could eventually spawn a regular-production model aimed largely at developing nations like India and Brazil.