US auto giant General Motors intends to close one or two factories in Europe in order to boost profitability at its loss-making Opel unit, the Wall Street Journal reported on Friday.

Quoting sources familiar with the plans, the newspaper said GM would make its decision public "within the next couple of weeks", with Opel's supervisory board set to consider plant closures at a meeting next week.

Neither GM nor Opel was willing to comment on the report when contacted by AFP.

But an industry source said "it is necessary for Opel to become profitable on a lasting basis" and the options for doing so "are not numerous".

GM's European operations have run up billions of dollars in losses over the past 10 years and it believes shutting down factories on both sides of the Atlantic as critical to restoring profitability in the region.