US President Donald Trump on Tuesday threatened to intensify sanctions on Iran, as hopes dimmed among world leaders gathered at the United Nations for a breakthrough in reducing tensions.
The leaders of France, Germany and Japan and Pakistan were all meeting separately with Trump and Iran's Hassan Rouhani, fanning speculation that the pair -- whose nations have been arch-enemies for four decades -- could have a historic encounter in New York.
But in a speech full of praise of unilateralism and criticism of China, Trump made clear he would not ease economic pressure on Iran -- a condition set by Rouhani for any meeting.
"As long as Iran's menacing behavior continues, sanctions will not be lifted. They will be tightened," Trump told the General Assembly.
After fiery speeches from the world body's rostrum in his first two years in office, Trump appeared subdued, reading slowly from script, just as a scandal escalated over accusations he pressured the president of Ukraine to investigate the son of former vice president Joe Biden.
Trump denounced Iran for an attack earlier this month on Saudi Arabia's oil infrastructure -- a day after European powers agreed with US findings that Iran was to blame.
"All nations have a duty to act. No responsible government should subsidize Iran's bloodlust," Trump said.
European powers, while criticizing Iran, want to salvage a 2015 accord under which Iran dramatically scaled back its nuclear program in exchange for unmet promises of sanctions relief.
last year pulled out of the agreement and imposed punishing sanctions, which
Iran has said it wants lifted before any high-level dialogue.
German Chancellor Angela Merkel, after meeting both Rouhani and Trump, said that Iran's condition on sanctions was "unrealistic."