Banks sought arbitration or court proceedings to recover dues under complex options positions sold to Ceylon Petroleum Corporation, after it refused to pay up when oil prices collapsed in 2008.
Sri Lanka's central bank has said the deals were tainted. The derivatives were sold by Standard Chartered, Deutsche Bank, Citibank and Sri Lanka's state-run People's Bank and listed Commercial Bank.
The value of the contracts have been variously valued at around 400 million dollars in various reports.
Citibank filed for arbitration in Singapore, but there is no decision on the case yet.
"The order has been reserved," attorney general Mohan Peiris said. "We just put in our written submissions.
A case filed by Standard Chartered Bank in London will be taken up again on Thursday, Peiris said.
Sri Lanka's Central Bank slapped a