UPDATE 1-S.Africa's new ANC leader Ramaphosa aims to fight corruption

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JOHANNESBURG, Dec 21 (Reuters) - Cyril Ramaphosa, the new leader of South Africa's governing ANC party, said on Thursday he aims to stamp out corruption and pursue a policy of "radical economic transformation" that will speed up expropriation of land without compensation.

Ramaphosa, a 65-year-old union leader who became a businessman and is now one of South Africa's richest people, is likely to become the country's next president after elections in 2019, because of his party's electoral dominance.

He has promised to fight rampant corruption and revitalize the economy, a message hailed by foreign investors.

"This Conference has resolved that corruption must be fought with the same intensity and purpose that we fight poverty, unemployment and inequality," he said in his maiden speech at the close of a five-day party meeting at which he was elected.

"We must also act fearlessly against alleged corruption and abuse of office within our ranks," Ramaphosa said in the early hours of Thursday after a long delay.

Ramaphosa's victory over former cabinet minister Nkosazana Dlamini-Zuma is seen as a pivotal moment for the ANC, which launched black-majority rule under Nelson Mandela's leadership 23 years ago but is now deeply divided with its image tarnished.

Ramaphosa paid tribute to President Jacob Zuma, who had backed his ex-wife Dlamini-Zuma for ANC's top job. Zuma's presidency, tainted by corruption and scandal, has badly tarnished the ANC's image both at home and abroad. The party once led by Nelson Mandela is now deeply divided.

However, investors are concerned that Ramaphosa may not be able to push through policy changes because the ANC's top decision-making group, known as the "Top Six," was split down the middle, consisting of three politicians apiece drawn from Ramaphosa's camp and that of his rival Nkosazana Dlamini-Zuma. (Reporting by Alexander Winning; Writing by James Macharia; Editing by James Dalgleish)