In an open letter to Donald Trump on Wednesday, 51 former U.S. officials and Iran experts called on the President of the United States to increase pressure on Iran.

"Now is the time to double down on the maximum pressure campaign to force the mullahs to spend their money on the Iranian people, not their nuclear ambitions, imperialism, and internal oppression," the signatories of the open letter said, in view of "reports that Tehran continues to plot attacks targeting U.S. forces".

While the maximum pressure campaign has seriously weakened the Islamic Republic’s ability to "generate revenue to support its malign activities", Iran is still able to draw on billions of escrowed oil dollars to fund humanitarian imports, the letter said adding that Supreme Leader Ali Khamenei has billions of dollars of money "stolen from the Iranian people" in his business empire that he can use on such activities.

Referring to the coronavirus crisis the signatories of the letter said the scale of the crisis in Iran has nothing to do with U.S. sanctions and attributed it to the "regime's mendacity in addressing the pandemic" and rejecting multiple offers of assistance from the U.S. government.

Iran was the second country in the world with a major coronavirus epidemic. Since February 19 when the two first deaths from COVID-19 were officially announced thousands have died.

Tensions have been particularly high between Iran and the United States since Iran's satellite launch on April 24 and the recent moves of the Revolutionary Guard in the Persian Gulf. Iranian military officials are vehement Iran will continue launching more satellites. The Guards Commander General Hossein Salami on April 22 said the launch of the satellite makes Iran a world power.

In a tweet on April 23 the U.S. National Security Council also said "No one should feel sorry for the [Iranian] regime. Iran cannot be allowed to develop intercontinental ballistic missiles".

Iran insists that its nuclear and satellite launch programs are peaceful.