WHAT do you get if you cross a Mini with an Alfa Romeo? No it's not a joke, Mini owner BMW really is joining forces with Alfa Romeo maker Fiat to build cars together.

The idea is to reduce development costs and help the Italian company reintroduce its Alfa Romeo brand in the US, where the Cowley-built Mini is enjoying a wave of popularity.

The two companies have agreed to explore joint "architectures and components" for Alfa Romeo and BMW's Mini division. Details of the project will be announced by the end of the year.

The economic downturn, coupled with soaring oil and steel prices - and tighter environmental regulations - are forcing carmakers to link up, particularly for smaller brands such as Mini.

The move follows announcement by PSA Peugeot Citroen, Europe's second-biggest automaker, and Mitsubishi Motors Corp, who said last month that they may develop electric vehicles together, a week after they started construction of a joint car plant in Russia.

The Mini is particularly popular with younger drivers, a market which car manufacturers are keen to tap.

Friedrich Eichiner, of BMW, said the agreement aimed "to achieve economies of scale and thus cost reductions".