South Korea\'s telecom titan KT Corp. said Friday that it has signed a preliminary agreement to acquire a 20-percent stake in Telkom SA Ltd., a South African telecom company. If finalized, Telkom will issue new common shares and KT will pay 36.06 South African rand per common share, it said in a release. The deal will be worth US$600 million and is part of a broader strategic partnership between the two telecom companies, KT said. KT is South Korea\'s dominant fixed-line operator and the second-biggest mobile carrier.