Venezuela's state-owned oil company PDVSA plans to increase the use of digital currencies in its crude and fuel exports as the United States reimposes oil sanctions on Venezuela, according to three people familiar with the matter. The U.S. Treasury Department last week asked PDVSA's customers and suppliers to end transactions by May 31. The move will make it harder for Venezuela to increase oil production and exports because companies will have to wait for individual U.S. authorizations to do business with Venezuela. PDVSA has been slowly accepting USDT, or Tether, whose value is pegged to the U.S. dollar, in oil sales since last year. The people familiar with the matter said the restoration of oil sanctions is accelerating the shift, a move to reduce the risk that sales revenue will be frozen in foreign bank accounts due to sanctions.