Uganda’s central bank on Wednesday asked investors holding Treasury bonds due to mature in April to apply to convert their holdings into longer-dated tenures to come due between May 2025 and August 2042.

The bank did not give reasons for the bond switching in which investors are free to choose whether to participate or not.

The east African country has been struggling with a rising public debt pile. In December, the bank said the surging costs of servicing Uganda’s public debt was putting undue pressure on public finances.

The Bank of Uganda (BoU) said investors holding the bonds maturing in April, which have a coupon rate of 11% can now apply to convert their holdings to the various longer-dated tenures with coupon rates ranging between 14% to 18.5%.

The new tenure options that investors can switch to include a three-year, five-year, ten-year, fifteen-year and twenty-year bonds, the bank said in a statement.

Auctions for the bond switch will be held on Feb. 6 and Feb. 8, according to the central bank.