Iran is still selling oil despite US sanctions on Tehran’s exports, showing the Trump administration's "maximum pressure" campaign had failed, Vice President Eshaq Jahangiri said on Monday. “Despite America’s pressure and its imposed sanctions on our oil exports, we still continue to sell our oil by using other means when even friendly countries have stopped purchasing our crude fearing America’s penalties,” Mr Jahangiri told state TV. He said that the Iranian people had resisted economic pressure. “They have failed to bring our oil exports to zero as planned,” Mr Jahangiri said. Iran holds around 9 per cent of the world’s known oil reserves and 16.2 per cent of its gas. While it was one of the worlds largest producers, underinvestment has seen it lag behind and slide down the rankings in recent years. Iran-US relations sunk to a new low last year after US President Donald Trump abandoned a 2015 deal in which world powers agreed to lift sanctions on Tehran in exchange for limits on its nuclear programme. US Secretary of State Mike Pompeo told an event in Kentucky on Monday that sanctions on Tehran had been effective, making the country poorer and hampering its trade with the rest of the world. “The good news is, in spite of what the world told President Trump, that American sanctions would not work, the world was wrong," Mr Pompeo said. "The sanctions have been incredibly effective." Washington has reimposed sanctions aimed at halting all Iranian oil exports, saying it wanted to force Iran into negotiating for a wider deal. But other world powers that signed the 2015 nuclear deal have not reinstated their sanctions. Tehran has rejected talks unless Washington returned to the nuclear deal and lifts all sanctions. Earlier on Monday, six European countries joined Instex, the bartering system allowing Iran to trade while avoiding sanctions, but they urged Tehran to stop breaching the 2015 deal. Iran wants Instex to include its oil. Washington has not warmed to the idea but some European officials have said that oil may be able to be added if Tehran complies with the nuclear accord.