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".

Trump says US will work closely with Iran, discuss sanctions
Lebanon undergoes heaviest Israeli bombardment since war began
US and Iran agree to truce; huge strikes on Lebanon as Israel escalates
Israel issues new evacuation order for Tyre in southern Lebanon
Greece to ban social media for under-15s from 2027, PM says
Israel backs Trump's two-week pause on Iran strikes, says Lebanon excluded
Bahrain reports damaged houses due to fallen debris
Trump says he has agreed to two-week ceasefire with Iran
