Financial sources say there has been strong interest for the bond. Orders open in Asia and move to Europe and close in the US as market open across the Atlantic.
Last year more than half the bond was sold to US investors.
The proposed bond has been rated 'BB- (exp)' by Fitch, 'B+' by Standard and Poor's and '(P)B1' by Moody's, all in the speculative grade.
Sri Lanka is repaying its maiden 500 million US dollar sovereign bond in October.