In September, Telkom received a non-binding proposal from Rain, which wanted Telkom to buy it in exchange for new shares in Telkom.

"After initial discussions, but prior to any due diligence, the parties have decided that a suitable transaction is not possible at this time," Telkom said.

Telkom's shares were up about 12% on the Johannesburg Stock Exchange at 1114 GMT.

(Reporting by Anait Miridzhanian; Editing by Alexander Winning)