Mali has been unable to pay almost $80m (£60m) it owes on an international debt after sanctions imposed in January froze its foreign bank accounts.
The country's total debt defaults since January have now reached $180m. The West African regional bloc, Ecowas, ordered the sanctions after Mali's military rulers went back on plans to hold elections and said they would stay in power for five years.
The Malian authorities have said the restrictions - and the cutting of foreign aid - were inhumane and will push people into deeper poverty.