Cuba says it has been forced to close most of its consular services in the United States because no bank will take its business.
The Cuban Interests Section in Washington said the M&T Bank had informed it in July that it would no longer provide banking services to foreign missions.
Havana's diplomatic mission said it had been impossible to find a replacement.
It blamed long-standing US economic sanctions against the communist island.
Officials at M&T Bank did not comment.
Washington and Havana broke diplomatic relations in 1961, but since 1977, they have had "interests sections" in each other's capitals under the legal protection of Switzerland.
Havana also has a Permanent Mission to the United Nations in New York.
The Cuban Interests Section said in a statement: "Despite the numerous efforts made with the State Department and several banks, it has been impossible to find a US or international bank with branches in the US to operate the bank accounts of the Cuban diplomatic missions."
It blamed restrictions derived from the US blockade of Cuba - first imposed by the Kennedy administration in the early 1960s.
Until further notice, said the statement, consular services including passport and visa processing would "only be provided in humanitarian cases and other of specific nature".
It also said it regretted the effects the move may have on family visits, academic, cultural and other exchanges between Cuba and the US.
Tourism sources in the United States say about 350,000 Cuban Americans visit the island every year. They all need an entry visa.
And Cubans without US citizenship must keep their Cuban passports up to date through the interests section in Washington, paying a renewal fee every two years of $200 (£124).