Iran's supreme leader Ayatollah Ali Khamenei said in a statement read by a television presenter on Wednesday that his country will not accept US President Donald Trump's call for an unconditional surrender.
In his first remarks since Friday, when he delivered a speech broadcast on state media after Israel began bombarding Iran, Khamenei said peace or war could not be imposed on the country.
"The Americans should know that any US military intervention will undoubtedly be accompanied by irreparable damage," he said.
Thousands of people were fleeing Tehran on Wednesday after Israeli warplanes bombed the city overnight, and a source said Trump was considering options that include joining Israel in attacking Iranian nuclear sites.
Israel's military said 50 Israeli jets had struck around 20 targets in Tehran overnight, including sites producing raw materials, components and manufacturing systems for missiles.
A source familiar with internal discussions said Trump and his team were considering a number of options, which included joining Israel in strikes against Iranian nuclear sites.
Iran had conveyed to Washington that it would retaliate against the US for any direct participation, its ambassador to the UN in Geneva, Ali Bahreini, said. He said he already saw the US as "complicit in what Israel is doing".

King Charles to host AI executives as threat fears mount
Amazon pauses operations with 21 Air after Miami cargo plane crash
Eleven injured in ammonia gas leak at Jordan's Aqaba industrial complex
Voting starts in Philippines' south after three killed in election violence
Italy's Catania airport shuts again as Etna ash halts flights
Indonesia rescuers battle turbulent seas in search for 129 people after ship capsizes
Trump tells Ukraine's Zelenskyy to stop hitting Russian diesel
Saudi Arabia lifts warnings of potential danger in four cities
