Royal Bank of Scotland has suspended its head of rates trading in Europe and Asia Pacific, the most senior employee to be put on leave so far as the bank investigates its alleged role in the interbank lending rate scandals. Jezri Mohideen was suspended last week as part of the bank's continuing investigation into the interbank rate-setting affair, according to two people close to the bank. RBS dismissed four traders last year but Mr Mohideen is the most senior employee and thefirst senior manager to be put on leave. He was head of rates trading in Europe, the Middle East,Africa and Asia Pacific. RBS declined to comment on Mr Mohideen's case but said in a statement: "Ourinvestigations into submissions, communications and procedures relating to the setting of Libor and other interest rates are ongoing. RBS and its employees continue to co-operate fully with regulators." Mr Mohideen could not be reached for comment. The bank has not requested a suspension of his authorisation by the Financial Services Authority, people close to the situation said. The news comes at a difficult time for RBS after the collapse of a deal to sell more than 300 bank branches to Spain's Santander. The bank is braced for a large penalty from regulators over its alleged involvement in the attempted manipulation of Libor, the interbank borrowingbenchmark, following the £290m fine handed down to Barclays this year. Recent court filings by a former Singapore-based trader at RBS have placed the bank under fresh scrutiny over alleged attempts to manipulate Libor. In papers filed at the high court in Singapore in recent months Tan ChiMin -- also known as Jimmy Tan -- said it hadbeen part of his duties toprovide the bank's Liborrate-setters with "input" and that RBS had condoned the practice. Mr Tan was dismissed bythe bank late last year for alleged gross misconduct relating to the setting of Libor. He issuing the bank for wrongful dismissal.