Iran slams US plan to blacklist Muslim Brotherhood

"The United States is supporting the biggest terrorist in our region, and that is Israel," Zarif told reporters on the sidelines of the Asian Cooperation Dialogue in Doha.

"Trying to designate others as terrorists, the United States (is) not in a position, theoretically and practically, to start naming others as terrorist organisations," he said when asked about US President Donald Trump's bid to designate the Brotherhood as a terrorist group.

"We reject any attempt by the United States in this regard."

In April, the US declared Iran's elite Revolutionary Guards a "foreign terrorist organisation".

The Brotherhood, a nearly century-old Islamist movement born in Egypt with pockets of support across the Arab world, was designated a terrorist organisation by Cairo after the military in 2013 ousted Mohamed Morsi, a democratically elected president with roots in the movement.

Placing the Brotherhood on Washington's list of foreign terrorist organisations would make it a crime for any American to assist the group and would ban from the United States its members, who are active in political parties in several countries.

The terrorist designation would delight Egypt's President Abdel Fattah al-Sisi as well as Saudi Arabia, which despite its ultra-conservative Wahhabi ideology disdains the Brotherhood due to its support for political change in the kingdom, including over Riyadh's alliance with Washington.

Egypt made peace with top US ally Israel 40 years ago and remains one of the largest recipients of US aid, at more than $1 billion a year.

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