US President Donald Trump urged Iran to negotiate a nuclear deal or face a harsher military strike, reported Reuters.

The aircraft carrier USS Abraham Lincoln and supporting warships had arrived in the Middle East after moving from the Asia-Pacific region last week. Two US officials confirmed the deployment.

The naval build-up comes amid heightened tensions following Iran's crackdown on protests. Trump has threatened intervention if Tehran resumed its nuclear programme after June airstrikes by Israeli and US forces on key installations.

In a social media, President Trump said Iran must "come to the table" for a fair agreement banning nuclear weapons. He warned that "the next attack will be far worse" and repeated that a US naval armada was heading toward the Islamic Republic.

The US withdrew from the 2015 nuclear accord during Mr Trump's first term and noted his last warning to Tehran was followed by a military strike in June.

Iran's mission to the United Nations responded that the US had squandered US$7 trillion and lost more than 7,000 lives in past wars in Afghanistan and Iraq. It said Iran stood ready for dialogue but would defend itself "like never before" if attacked.

Iranian Foreign Minister Abbas Araqchi told state media he had not been in contact with US special envoy Steve Witkoff or requested negotiations in recent days.