BERLIN – Former Russian oil tycoon Mikhail Khodorkovsky has travelled to Switzerland after receiving a three-month visa for the Alpine country.

His spokesman Christian Hanne says Khodorkovsky and his wife went to Switzerland by train Sunday from Germany to accompany their two sons, who were returning to their Swiss school.

Khodorkovsky was pardoned Dec. 20 after spending more than a decade in Russian prisons after receiving a conviction the West considered political revenge for his challenging Russian President Vladimir Putin. He then flew immediately to Berlin.

Days later, Khodorkovsky applied for a visa to Switzerland, a country he long had business ties to.