The man, who has not been identified, was said to be “safe and well” after his ordeal in the industrial city of Dnipropetrovsk in southern Ukraine.
Ukraine’s Security Service (SBU) said the Briton – who was traveling alone – checked in to a local hotel on March 3, but two days later made a call to relatives in Britain to say he was being held against his will by people demanding a ransom.
His frightened family contacted the British embassy in Kiev, which got in touch with Ukrainian authorities.
The SBU established the whereabouts of the victim and his three abductors the same day, and dispatched members of its elite Alpha special operations unit to intercept them.
The British citizen and the three alleged kidnappers were stopped in a car traveling from Dnipropetrovsk toward Kharkov in the northeast of the country.
Igor Volovik, an SBU spokesman, said: “The man was a tourist. His kidnappers demanded $30,000 [£20,000] from his relatives for his release. The money was supposed to be passed via an electronic money transfer system. The man was freed by Alpha officers and the three kidnappers are under arrest.”
Mr Volovik refused to give further details while a kidnapping investigation was ongoing. “He is safe and well and still in Ukraine, helping with enquiries,” he said.
A spokesman for the British embassy in Kiev confirmed that the man was unharmed but also refused to name him.
An FCO spokesman said: “We are aware of the situation and have been providing consular assistance.”