* S.African regulators accuse 16 banks of FX collusion
* Private pre-hearing with banks held on Friday - source
* Citigroup, Barclays cooperated in probe
* Some other banks set to oppose ruling - source (Adds further details, quotes, background)
By Joe Brock
JOHANNESBURG, March 10 (Reuters) - Sixteen banks accused of colluding to rig South Africa's rand currency could go before the Competition Tribunal to conclude the case in July, after a private pre-hearing was held on Friday, a source at the country's Competition Commission said.
The Commission said last month that it had found traders at more than a dozen local and foreign banks colluded to coordinate dealing in the South African and U.S. currencies.
All the banks named in the probe met on Friday with the Commission and the tribunal panel which will hear the case. Dates for hearings and possible arguments and objections against the ruling were discussed, the source said.
"It was cordial but clearly some banks are going to raise objections. Things are moving fast. A tribunal in July is possible but there could be delays," the source said.
Barclays and Citigroup previously approached South Africa's competition regulators with information linked to the case and Citigroup was fined 69.5 million rand ($5.25 million) last month for its role.
Citigroup will face a separate hearing on March 22 when the agreed fine is expected to be ratified as a final settlement, although the tribunal could recommend changes, the source said.
"Since we haven't had any more settlements we can assume the majority of banks are going to oppose the ruling," the source said.
The other banks named in the case are, Nomura, Standard Bank, Investec, JP Morgan, BNP Paribas, Credit Suisse Group, Commerzbank AG, Standard New York Securities Inc, Macquarie Bank , Bank of America Merrill Lynch (BAML), ANZ Banking Group Ltd and Standard Chartered Plc.
The Commission alleged that from at least 2007 traders had a general agreement to collude on prices for bids, offers and bid-offer spreads for the spot trades in relation to currency trading involving the dollar and rand currency.
Traders manipulated the price of bids and offers through agreements to refrain from trading and creating fictitious bids and offers at particular times, the Commission said. ($1 = 13.2275 rand) (Editing by Elaine Hardcastle, Greg Mahlich)