Bloomberg newswires said an initial price guidance of 9.25 percent has been set.
The bond is marketed by Barclays, Citigroup and HSBC.
NSB's road show ended last week but managers held off formally collecting orders amid elevated interest rates and bad sentiment over a plans by the US to attack Syria.
A dollar denominated bond by state-run Bank of Ceylon maturing in 2018 was quoted at 7.90/8.14 percent levels Thursday.
A 2020 sovereign bond was quoted around 7.32/55 percent levels bond dealers said.
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