Deutsche Bank, Germany's biggest lender, has suspended a top saleswoman in an investigation into suspected foreign exchange rate manipulation, the Wall Street Journal reported on Thursday. Quoting a person familiar with the matter, the newspaper said that the director of sales at Deutsche Bank in London was placed on leave last month after the German bank found what it regarded to be inappropriate communication between her and the central bank of Singapore. Responding to the report, a Deutsche Bank spokeswoman said: "Deutsche Bank has received requests for information from regulatory authorities that are investigating trading in the foreign exchange market. "The bank is cooperating with those investigations, and will take disciplinary action with regards to individuals if merited." For its part, the Monetary Authority of Singapore (MAS) said: "MAS has been in contact with foreign regulators and stands ready to assist in the forex investigations. We have been in touch with financial institutions, including Deutsche Bank, on these investigations. MAS is looking into all allegations of inappropriate behaviour." According to German media reports in January, Deutsche Bank, one of the biggest currency traders in the world, already suspended "at least one" currency trader -- based in New York and trading in Argentine pesos -- on suspicion of possible rigging of forex reference rates.