An Iranian girl poses with a potrait of the country's Supreme Leader Ali Khamenei with signs reading "Down with USA" and "Down with Israel" during a ceremony celebrating the 40th anniversary of Islamic Revolution by the capital Tehran's Azadi (Freedom) tower in the square of the same name on February 11, 2019.
The festivities to mark the Iranian Revolution start every year on February 1, the day that Khomeini returned from exile to become supreme leader of the Islamic republic.
"If this regime makes the terrible mistake of trying to destroy Tel Aviv and Haifa, it will not succeed", the Israeli leader said. Prime Minister Benjamin Netanyahu took note and responded: try it, and it will be the last Revolution Day the Iranians will ever celebrate.
"I don't ignore the threats from the Iranian regime, but I'm also not intimidated by them", Netanyahu said in a Hebrew-language video.
On Feb 11, 1979, Iran's army declared its neutrality, paving the way for the fall of Shah Mohammad Reza Pahlavi, the United States' closest ally in the Middle East.
State TV showed large crowds carrying Iranian flags and chanting "Death to Israel, Death to America", trademark chants of the revolution.
Speaking from a podium in central Tehran, Iranian President Hassan Rouhani addressed the crowds for almost 45 minutes, lashing out at Iran's enemies - America and Israel - and claiming their efforts to "bring down" Iranians through sanctions will not succeed.
"It has been moving forward over the past 40 years and making Iran stronger". 40 years of repression.
According to Channel 12 news, the factory is meant to focus on producing precision missiles, dramatically upgrading the threat to Israel from the vast arsenal of rockets and missiles deployed against it in southern Lebanon by Iran's proxy, Hezbollah. "The long-suffering Iranian people deserve a much brighter future", Trump posted on Twitter in both English and Farsi.
In the backdrop to Monday's marches, the military displayed Iranian-made missiles, which authorities showcase every year during anniversary celebrations and which now have a range of up to 2,000 kilometres (1,250 miles) and are able to Israel and USA military bases in the region.
Prices of basic foodstuffs have soared since President Donald Trump withdrew Washington from the 2015 nuclear deal in May 2019.
In January, Rouhani said Iran was dealing with its worst economic crisis since the Shah was toppled.
But if the United States does attack, he warned, "We will raze Tel Aviv and Haifa to the ground".
"The Iranian people have and will have some economic difficulties but we will overcome the problems by helping each other", he said.
Iran and Saudi Arabia are locked in proxy wars in Iraq, Yemen and Syria.
Elsewhere, the head of the elite Quds Force of Iran's powerful Revolutionary Guard, Gen. Qassem Soleimani, attended the rally in the southern city of Kerman.