The agency said it acted after a 30-day grace period had passed on payments on two bonds.
S&P said in a statement late on Monday that Venezuela had failed to make $200 million in coupon payments for its global bonds due 2019 and 2024 within the 30-calendar-day grace period, due on Sunday. But this week, one of the country's last vestiges of normalcy was erased when credit rating firm Standard & Poor's said the country was in default.
S&P's move came after Vice President Tareck El Aissami met with creditors in Caracas Monday, but offered no way out of the impasse.
Venezuela's state-run oil company PDVSA has also been declared in default by rating agencies Fitch and Moody's.
In the meantime, China said its massive financing of Venezuela was "proceeding normally", and Russian Federation was expected to sign an agreement as early as Wednesday to restructure $3 billion of Caracas's debt, according to sources in Moscow familiar with the matter.
Sensex flat with negative bias; Nifty trades at 10302
Meanwhile, the Nifty was trading lower by 19.75 points or 0.19% at 10,302.00 with 30 components falling. The loss in BSE capital goods was maximum at 1.41 per cent, followed by telecom, infrastructure and PSU.
But creditors who attended the meeting told journalists that the 25-minute meeting ended without the government making any concrete proposals. And many creditors also can't negotiate with El Aissami: He, too, is sanctioned by the US Treasury, which accuses him of drug trafficking.
Participants in the creditors' meeting said at least one attendee left the room when it became clear Mr Aissami would be leading it.
American investors can't participate in a restructuring anway, as sanctions prohibit them from receiving new bonds that Venezuela would issue.
Now, as United States sanctions cut deeper into what's left of the economy, it's increasingly unclear how Venezuela will support itself. He insisted, however, the OPEC nation would continue to service its debts.