CARACAS, Venezuela (AFP) — Venezuela struck a defiant note Wednesday, insisting that its crude oil exports were not impacted by United States (US) President Donald Trump’s announcement of a potentially crippling blockade.

Trump’s declaration on Tuesday marked a new escalation in his months-long campaign of military and economic pressure on Venezuela’s leftist authoritarian President Nicolas Maduro.

Venezuela, which has the world’s largest proven oil reserves, shrugged off the threat of more pain, insisting that it was proceeding with business as usual.

“Export operations for crude and byproducts continue normally. Oil tankers linked to PDVSA operations continue to sail with full security,” state oil company Petroleos de Venezuela (PDVSA) said.

Trump said Tuesday he was imposing “A TOTAL AND COMPLETE BLOCKADE OF ALL SANCTIONED OIL TANKERS going into, and out of, Venezuela.”

Referring to the heavy US military presence in the Caribbean — including the world’s largest aircraft carrier — he warned “Venezuela is completely surrounded by the largest Armada ever assembled in the History of South America.”

Oil prices surged in early trading on Wednesday in London on news of the blockade, which comes a week after US troops seized a sanctioned oil tanker that had just left Venezuela with over 1 million barrels of crude.

Maduro held telephone talks with UN Secretary-General Antonio Guterres to discuss what he called the “escalation of threats” from Washington and their “implications for regional peace.”

Guterres’s spokesman said the UN chief was working to avoid “further escalation.”