Missiles and a portrait of Iran's Supreme Leader Ayatollah Ali Khamenei on display at Baharestan Square in Tehran, Iran, September 27, 2017. Nazanin Tabatabaee Yazdi/TIMA via REUTERS/Files

TEHRAN: Iran on Sunday announced its fifth step back from a nuclear deal, saying it will forego the "limit on the number of centrifuges", amid mounting tensions with the United States.

The announcement came after a US drone strike Friday killed top Iranian military commander Qassem Soleimani in Iraq, sparking fury in Iran which has vowed to avenge his death.

Read more: Iran condemns Trump as 'terrorist in a suit' after attack threat

Earlier in the day, Iran condemned US President Donald Trump as a “terrorist in a suit” after he threatened to hit 52 Iranian sites hard if Tehran attacked Americans or the US assets in retaliation for Soleimani's killing.

As the two countries assailed each other in a war of words, the European Union (EU), Britain, and Oman urged the parties to seek to de-escalate the crisis.

Also read: Two rockets target Iraqi air base housing US troops

Soleimani, Iran’s pre-eminent military commander, was killed on Friday in a US drone strike on his convoy at Baghdad airport, an attack that took long-running hostilities between Washington and Tehran into uncharted territory and raised the spectre of wider conflict in the Middle East.

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