"International reserves rose thanks to stable and rhythmic inflows from international partners, which exceeded the net sale of currency by the National Bank and the country's debt payments in foreign currency," it said in a statement.
The central bank said it had received $4.23 billion last month, which included financial aid from the European Union, the United States and the World Bank as well as funds raised on the domestic debt market from placing government debt denominated in hard currency.
Ukraine, which is fighting a full-scale Russian invasion, also paid $842.2 million to service its foreign debts and $195.5 million to the International Monetary Fund.
The central bank also said its hard currency sales on the foreign exchange market grew to $1.9 billion in May.
Ukraine's hryvnia currency is officially pegged at 36.57 to the dollar and the central bank intervenes regularly to reduce the gap between the official hryvnia peg and cash market rate.
(Reporting by Olena Harmash, Editing by Timothy Heritage)
