* French court rejects E.Guinea appeals against graft probe
* E.Guinea leader's son suspected of diverting state funds
* Probe also looks at leaders of Gabon and Congo-Brazzaville
PARIS, June 13 (Reuters) - A French court upheld on Thursday an arrest warrant for the son of Equatorial Guinea's president on charges of money-laundering, a source familiar with the case said.
The Paris appeals court also ruled that a luxurious property seized last year as part of the probe should remain in the hands of French investigators, who suspect Equatorial Guinea's leaders of embezzling public funds to buy real estate in France.
Teodorin Obiang, the son of President Teodoro Obiang, is agriculture minister and second vice-president of the small African state, where a majority of the population lives in poverty despite rich oil reserves and forests. He also faces money-laundering charges in the United States.
Obiang has denied wrongdoing and said his wealth, which has allowed him to purchase luxury real estate in Paris and Malibu, a private jet and a stable of exotic sports cars, was amassed legitimately through successful business dealings.
The case against Teodorin Obiang is part of a broader investigation into money-laundering targeting the families of Gabonese President Ali Bongo and Congo Republic's President Denis Sassou-Nguesso. Together they are suspected of owning 63 luxury properties in Paris and some 200 bank accounts.
Last year, French police seized a building in a wealthy area of Paris allegedly owned by Teodorin, where they confiscated millions of euros of art, antiques and fine wines. The building, on Avenue Foch, was valued at 150 million euros ($199.49 million)and investigators said it housed a nightclub and hair salon.
Teodorin's lawyers have argued that the building did not belong to him and was used for diplomatic purposes. The judges rejected their claims.
"Once more, attempts by Equatorial Guinea to scrap the case have failed," said lawyer William Bourdon, of anti-corruption organisation Transparency International France, which filed the legal complaint.
Lawyers for Equatorial Guinea and for Teodorin Obiang were not immediately available for comment.
In September, Equatorial Guinea asked the International Court of Justice to rule that France should drop its investigation, cancel the arrest warrant and return seized property.
($1 = 0.7519 euros) (Reporting by Chine Labbe, Writing by Natalie Huet; Editing by John Irish and Michael Roddy)