China's Changsha municipal government has donated 40,000 medical-grade face masks to Annapolis, its sister city in the United States, local media reported.

The donation from Changsha, capital city of central China's Hunan Province, was first offered to officials of Maryland's capital city Annapolis in April, when the need for masks among public safety workers was at its highest in the early days of the COVID-19 pandemic, according to a statement by Annapolis City Manager David Jarrell.

The masks arrived in August, with one of the boxes featuring stickers of American and Chinese flags with a message reading: "Go, City of Annapolis! Best Wishes from Changsha! True unity inspires people to work as one to overcome adversity," the Capital Gazette newspaper reported.

"We sincerely wish you and everyone in Annapolis continued good health, and the fortitude to persevere during this challenging period," read a note accompanying the shipment from Changsha's Foreign Affairs Office.