Germany's Siemens on Tuesday drew a line under its costly venture into mobile handsets, selling its unit to BenQ in a deal that will see the Taiwanese electronics manufacturer become one of the world's five biggest makers of handsets.

Measured by the $5.8bn in revenue that Siemens' mobile business brought in last year, the deal is one of the largest acquisitions of a European business by an Asian company and the largest-ever cross-border takeover by a Taiwanese company.