The International Monetary Fund will send a mission to Zambia in May to continue talks over as much as $1.6 billion in aid the government is seeking after they failed to reach a deal in Washington this month.

“Progress was made but program discussions have not yet been concluded,” Alfredo Baldini, the fund’s representative in Zambia, said Friday in response to emailed questions by Bloomberg.

“The authorities and IMF staff have agreed that a mission will return to Zambia at the end of May to continue the discussions.”

Finance Minister Felix Mutati had hoped to strike the loan deal to boost Zambia’s foreign exchange reserves while in Washington for the IMF and World Bank Spring Meetings.

The government first signaled its intentions to sign a deal in 2014 but has faced a number of delays since.

Africa’s second-biggest copper producer has struggled with ballooning budget deficits in recent years as metal prices fell and government spending grew. A power crisis worsened the situation as government paid hundreds of million of dollars for electricity imports, while economic growth fell to the lowest since 1998.