JOHANNESBURG, Feb 17 (Reuters) - Barclays Plc and Citigroup approached South African antitrust investigators with information relating to alleged rigging of the rand, two sources told Reuters on Friday.
South Africa's Competition Commission said on Wednesday it had found more than a dozen local and foreign banks colluded to coordinate trading in the South African and U.S. currencies.
Its inquiry centred on an instant messaging chat room called "ZAR Domination", which the Commission alleged was used by the banks to coordinate trading activities when giving quotes to customers who buy or sell currencies.
The Commission launched the probe in April 2015, joining a global clampdown that has led to dozens of traders being fired and big banks fined a total of around $10 billion for rigging interest rate and foreign exchange benchmarks.
In the case of the alleged rigging of the rand, the Competition Commission said it had recommended fines amounting to 10 percent of the banks' South African annual revenues to the country's Competition Tribunal, which adjudicates on the watchdog's findings.
"Barclays and Citigroup offered to co-operate with the investigation," one source said, adding that if the information they provided led to a successful prosecution of other members of the alleged cartel they could be exempted from any fine.
Barclays reiterated on Friday a statement made earlier in the week in which it said it was cooperating with regulators, while Citigroup, which has also said it is working with regulators, was not immediately available for comment.
Barclays and Citigroup were not included in the list of banks that the Commission recommended should be fined, but it did name them as members of the alleged rigging group.
The Commission was not seeking any penalty against Citigroup, Barclays and Barclays Africa because of the information they supplied was enough to refer the matter to Tribunal for prosecution, another source said.
The information the banks provided, which the sources did not detail, would be examined by the Competition Tribunal.
The other banks and brokerages named in the case were, 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.
Investec and Barclays both have said they would cooperate with the probe, while Standard Bank, BAML, Commerzbank, BNP Paribas Nomura, Credit Suisse, ANZ, Standard Chartered and Macquarie declined comment. The others have not commented. (Editing by Alexander Smith)