Tehran has warned US allies in the Middle East it will strike US bases on their soil if Washington attacks Iran, a senior Iranian official told Reuters on Wednesday, following President Donald Trump's threats to intervene in support of protesters.

The death toll from Iran’s unrest climbed to almost 2,600, a rights group said, as the clerical establishment seeks to quell nationwide protests posing one of the biggest challenges to their rule since the 1979 Islamic Revolution.

According to an Israeli assessment, Trump has decided to intervene but the scope and timing of this action remains unclear, an Israeli official said.

The Iranian official, speaking on condition of anonymity, said Tehran had asked US allies in the region to “prevent Washington from attacking Iran”.

“Tehran has told regional countries, from Saudi Arabia and UAE to Turkey, that US bases in those countries will be attacked” if the US targets Iran, the official said.

The official added that direct contacts between Iran's Foreign Minister Abbas Araqchi and US Special Envoy Steve Witkoff had been suspended, reflecting mounting tensions.

A second Israeli source, a government official, said Prime Minister Benjamin Netanyahu’s security cabinet was briefed late on Tuesday about the chances of regime collapse or US intervention in Iran, an arch-foe with which Israel fought a 12-day war last year.

In an interview with CBS News on Tuesday, Trump vowed “very strong action” if Iran executes protesters. “If they hang them, you’re going to see some things,” he said. He also urged Iranians on Tuesday to keep protesting and take over institutions, declaring “help is on the way” but without giving details.

The United States has forces across the region including in Bahrain, home to the headquarters of the US Navy's Fifth Fleet, and Qatar, which hosts Al Udeid Air Base - the forward headquarters for US Central Command.

Iran fired missiles at Al Udeid last year in retaliation for US airstrikes on its nuclear installations.

It came after fighting across the border between Myanmar’s Arakan Army and armed Rohingya groups injured at least two Bangladeshi civilians.

Iran holds contact with Turkey, UAE, Qatar

Iranian state media reported that the head of Iran’s top security body, Ali Larijani, had spoken to the foreign minister of Qatar and Araqchi had spoken to his Emirati and Turkish counterparts. The countries are all US allies.

Araqchi told UAE Foreign Minister Sheikh Abdullah bin Zayed that “calm has prevailed” and that Iranians were determined to defend their sovereignty and security from any foreign interference, state media reported.

The flow of information from Iran has been hampered by an internet blackout.

US-based HRANA rights group said it had so far verified the deaths of 2,403 protesters and 147 government-affiliated individuals. An Iranian official told Reuters on Tuesday that about 2,000 people had been killed.

Iranian authorities have accused the United States and Israel of fomenting the unrest, blaming violence on people it calls terrorists who have attacked security forces, mosques and public property.

Iran’s chief justice urges swift actions

Visiting a Tehran prison where arrested protesters are being held, Iran’s chief justice said speed in judging and penalizing those “who beheaded or burned people” was critical to ensuring such events do not happen again.

HRANA reported 18,137 arrests so far.

State TV said that a funeral procession would take place on Wednesday in Tehran for more than 100 civilians and security personnel killed in the unrest.

Hengaw, an Iranian Kurdish rights group, has reported that a 26-year-old man, Erfan Soltani, arrested in connection with protests in the city of Karaj, was to be executed on Wednesday.

Hengaw told Reuters on Wednesday it had not been able to confirm whether Soltani's sentence had been carried out due to the internet and communications shutdown. Reuters could not independently confirm the report.

Pro-government rallies were held in Iran on Monday, a show of loyalist support for the clerical Iranian establishment. So far, there have been no signs of fracture in the security forces that have quelled other bouts of protest over the years.

While Iranian authorities have weathered previous protests, the latest unrest is taking place with Tehran still recovering from last year’s war, and with its regional position weakened by blows to allies such as Lebanon’s Hezbollah since the October 7, 2023 Hamas-led attacks against Israel.

Asked what he meant by “help is on its way”, Trump told reporters on Tuesday they would have to figure that out. Trump has said military action is among the options he is weighing to punish Iran over the crackdown.

“The killing looks like it’s significant, but we don’t know yet for certain,” said Trump upon returning to the Washington area from Detroit, adding he would know more after receiving a report on Tuesday evening.

Trump on Monday announced 25% import tariffs on products from any country doing business with Iran - a major oil exporter.

The US State Department on Tuesday urged American citizens to leave Iran now, including by land through Turkey or Armenia.