BERLIN- The German government declined to give an update on Monday of its review of the planned sale of chip supplier Siltronic to Taiwanese rival GlobalWafers, which needs Berlin's approval to complete the deal.

Germany's Federal Ministry for Economic Affairs and Climate Action must approve the 4.35 billion euro ($4.97 billion) sale, agreed about a year ago, by Jan. 31. Otherwise the transaction will collapse. 

"I cannot comment on the details of investment appraisals as a matter of principle," a spokesperson for the ministry told a regular government news conference in Berlin. "That also applies to the duration."

The spokesperson added that such investment review procedures often involve very complex issues.

Siltronic said on Friday that Germany's approval of the sale was still outstanding. 

GlobalWafers secured a majority stake in Siltronic last year and initially hoped to have the transaction, which aims to create the world's second-largest maker of 300-millimetre wafers, wrapped up in late 2021. 

($1 = 0.8760 euros)

(Reporting by Paul Carrel, Editing by Miranda Murray) ((