Prema sporazumu postignutom s italijanskom firmom Eni, drugim sudioničarom u zajedničkoj investiciji za izgradnju gasovoda, kapacitet Južnog toka povećan je s početno planiranih 31 milijardu kubnih metara gasa godišnje na 63 milijarde kubnih metara.
Under the deal reached with Italy's Eni, the other co-shareholder in a joint venture to build the pipeline, South Stream's capacity was increased from the initially planned 31 billion cubic metres of gas a year to 63 billion cubic metres.