MUMBAI: Amitabh Bachchan surprised fans by wishing them Merry Christmas on January 7. The actor then explained on social media that this is the date of the Russian Christmas as per the Gregorian calendar.

"Merry Christmas .. Russian Christmas on Jan 7 .. Christmas holiday-January 7th in the Gregorian calendar or December 25, Julian calendar ... as informed by Alla Yukhina, Russian Ef," tweeted Bachchan from his verified account.

Fans from across the world reciprocated to the tweet by wishing the actor on Orthodox Christmas.

"Thank you, Amit Ji! You remember and respect the Russian-speaking population all over the world. They love you very much in Russia! Movies are shown with translation. However, not always the timbre of the voice coincides with yours. So I'm reviewing movies in Hindi," commented a fan from Crimea.

"Merry Christmas and Happy New Year 2021 to all Orthodox Christians who celebrate Christmas on 7th Jan... Greetings and wishes," shared another fan.

On Wednesday, the actor had shared a photograph clicked in Moscow, Soviet Union in 1990-91, where he is seen mobbed by fans for autograph.

On the work front, Big B will feature in upcoming films like "Chehre", Nagraj Manjule's "Jhund", Ayan Mukerji's "Brahmastra", Ajay Devgn's "Mayday" and a yet untitled film co-starring Prabhas and Deepika Padukone.