Dupont Circle residents are planning a protest Tuesday over what they call an embassy’s illegal move to pave over the front yard of its historic 16th Street mansion. The property’s sovereign status, though, likely leaves them with little legal recourse.

The Republic of Congo bought the property, known as the Toutorsky Mansion, from a private owner who unsuccessfully tried to turn it into a bed and breakfast. The Congolese government received zoning approval in March to operate the 1890s mansion as an embassy, but only after the republic withdrew its request to turn the front yard into a half-circle driveway.