Nigeria's external debts have risen to 11.26 billion U.S. dollars as of the end of June this year, representing an increase of more than 9 percent from 10.32 billion U.S. dollars registered a year ago, the Nigerian Debt Management Office has said.

Meanwhile, latest data from the agency also revealed that domestic debt also increased to 10.61 trillion naira as of the end of June from 8.4 trillion naira (more than 27 billion dollars) a year go, representing an increase of 26 percent.

Noting that maturing debts will have to be refinanced at official interest rates, the Debt Management Office said refinancing 30 percent of the government's domestic debt within the next one year might pose a high risk to the economy.

The country on Tuesday retained its double-digit interest rate at 14 percent.