The bond sale will be Panama's first overseas activity since the country's sovereign debt was upgraded to investment grade earlier this year by all three major ratings agencies.
The bond, in yen-dominated debt, is aimed only at Japanese institutional investors and is likely to be issued in January 2011. The government is hoping to increase its presence in Asian markets and reduce its borrowing costs.
Poland has also started marketing three-year and five-year samurai bonds to be sold this month. The move follows issuance of samurai bonds last month by Mexico and Indonesia of ¥150bn ($1.8bn) and ¥60bn, respectively. According to data from Bloomberg, emerging economies have raised a total of at least ¥310bn through the sales of samurai bonds this year.