The German government made an unprecedented request of Belgium to temporarily shut two nuclear reactors, citing technical issues involving possible safety defects.

Germany asked Belgium to take Engie SA's Tihange-2 and Doel-3 atomic plants offline until the safety concerns can be addressed, Environment Minister Barbara Hendricks said Wednesday in an emailed statement. The two facilities, which were shut for investigations for 20 months, are safe to operate, Belgium's nuclear regulator AFCN said in response to the request.

"We've never made such a request to a neighboring state before," Deputy Environment Minister Jochen Flasbarth told reporters on a conference call. "This is an unusual procedure."