MOSCOW (AP) — The brother of an American being held in Moscow for alleged spying says a prison visit by U.S. Embassy staff has been postponed.

David Whelan expressed disappointment that Russian authorities didn't allow the visit scheduled for Thursday, but said he hoped it could be rescheduled soon and British diplomats also would be given access to his twin brother, Paul.

Paul Whelan lives in Michigan and holds citizenships from the U.S., Britain, Ireland and Canada. Russia promised to permit consular visits while he is imprisoned.

David Whelan says a Wednesday visit by Irish officials "was very helpful and gave us an opportunity to receive specific guidance from Paul."

He says the visits "will help ensure his continued health and well-being while the family continues to work with government officials to try to bring Paul home."