Belgium's financial-market regulator Tuesday said it has extended for an "indefinite period" restrictions on short-selling securities.

The regulator, the CBFA, said the rules won't apply to transactions in shares or instruments related to ING Group NV (ING), since the bank has its primary listing in the Netherlands.

-By Adam Cohen, Dow Jones Newswires; +322 741 1486; adam.cohen@dowjones.com