Venezuelan government has decided to cancel currency notes of 100 bolivar within 72 hours.
The move was made to stop black marketing of the currency which government belives is about 300 bn bolivars.
Central bank data suggests there are more than six billion 100-bolivar notes in circulation, making up almost half of all currency.
Venezuelans will have 10 days from Wednesday to exchange the notes for coins and new, higher-value bills.
President Nicolas Maduro said the move would stop gangs hoarding the notes.