Iraq's parliament on Sunday called for the expulsion of USA troops from the country in the wake of the attack in Baghdad that killed Soleimani. At issue is the fate of the agreement under which Washington sent troops to Iraq more than four years ago to help in the fight against the Islamic State group.
The parliamentary resolution was passed by overwhelmingly Shi'ite lawmakers, as the special session was boycotted by most Sunni Muslim and Kurdish lawmakers.
The German Foreign Minister also proposed to hold a regular meeting with his counterparts from other European Union countries amid growing tensions in the Middle East.
Johnson said he would not lament the death of someone who played a leading role in actions that led to the deaths of thousands of innocent civilians and Western personnel, but that "calls for retaliation or reprisals will simply lead to more violence in the region and they are in no one's interest".
It comes as Boris Johnson tried to distance Britain from the U.S. as Donald Trump ramped up his rhetoric against Iran, threatening to target cultural sites.
"Like ISIS, Like Hitler, Like Genghis!"
Iran's supreme leader vowed "severe revenge" but first declared three days of national morning, which conclude on Monday night. "Trump is a "terrorist in a suit", Jahromi wrote on Twitter.
"Trump may not care about the laws of war, but DoD (Department of Defense) planners and lawyers do. and targeting cultural sites is war crime". It was not immediately clear whether there were USA casualties.
"We are ready to continue our support if it is desired and the situation allows it", Maas said.
Nicholas Burns, who served as USA ambassador to North Atlantic Treaty Organisation under president George W Bush, said the Trump administration would be guilty of hypocrisy given it was part of worldwide efforts to deter Daesh from destroying countless pre-Islamic artefacts, including in the Syrian UNESCO-listed site of Palmyra.
Heightened fears of war drove Gulf stocks sharply lower on Sunday.
Iran announces new step to distance itself from 2015 nuclear deal with major powers.
In a statement it said it would no longer observe limitations on its capacity for enrichment, the level of enrichment, the stock of enriched material, or research and development. Trump vowed to hit Iraq with crippling sanctions in response.
The announcement came Sunday night after another Iranian official said it would consider taking even-harsher steps over the U.S. killing of Soleimani. It said the roll-back of its nuclear commitments could be reversed if the United States lifted sanctions on Tehran.