The leader of Venezuela's National Assembly has threatened that a later government may refuse to pay $2.8 billion in bonds that Goldman Sachs recently purchased from the country's central bank.

"It is apparent Goldman Sachs decided to make a quick buck off the suffering of the Venezuelan people," Julio Borges, the leader of the opposition-controlled congress , said in a letter dated on Monday to Goldman CEO Lloyd Blankfein.

"Given the irregular nature of this transaction and the absurd financial terms involved that are to the detriment of Venezuela and its people, the National Assembly will soon launch an investigation into the matter. I also intend to recommend to any future democratic government of Venezuela not to recognize or pay on these bonds," Borges wrote.

Julio Borges: Toda deuda que adquiera la Nación sin aprobación de la @AsambleaVE será INEXISTENTE

The terms of the bond deal, reported this week by the Wall Street Journal, citing people familiar with the transaction, called for Goldman to pay around $865 million for $2.8 billion in bonds issued by the state oil company Petroleos de Venezuela, or PDVSA, in 2014, maturing in 2022, working out to around 31 cents on the dollar and implying an annual yield above 40 percent.

Borges said the deal offered a "financial lifeline" to President Nicolas Maduro's regime, which has been accused using violence against frequent protests.