The CEO of a Christian charity that works in the Middle East has told Premier they are having to think carefully about how to move their staff around Iraq safely and advised Christians to contact their MP to ask them to have a positive influence on the situation.
On Friday, American President Donald Trump launched a drone strike on Iraq which hit Iranian General Qassem Soleimani, who he claimed was plotting terrorist acts.
Mr Trump has also announced he will send in 3,000 more troops to the region. Iraqis have seen the US's move as one of interference; despite many feeling Iran does have too much control in Iraq.
On Saturday, thousands of people marched in a funeral procession in Baghdad, the capital of Iraq, in protest at America's actions.
Iran has threatened retaliation.
The Foundation for Relief and Reconciliation in the Middle East (FRRME) is a Christian charity that works on peace relations and helping vulnerable communities.
FRRME's CEO Mike Simpson told Premier the charity has staff across Iraq and Jordan: "We've been in conversation with those people yesterday morning and are continuing to be in conversation with them...people are in fear of future events.
"The overnight actions that have followed on from the killing of this man have exacerbated that [fear]. There have been other attacks that look like American attacks, or perhaps through the Iraqi forces, we're not quite sure, that have killed others connected with the Shia Iranian-backed militias.
"It seems like a concerted effort to really crush or, at least, gravely injure the power of those militias in Iraq. Iranian interference in Iraq is a big problem - that is why there have been huge protests across Baghdad and other cities over the last few months, because people are fed up with the Iranian influence in Iraq. But this situation that's arisen over the last 48 hours really does stoke the fires.
"One US politician has talked about throwing a stick of dynamite into a tinderbox. Another person in the UK said 'could this be like a Franz Ferdinand moment that started the First World War?' Let's hope that neither of those are true. But people are very worried."
Mr Simpson said the Foundation for Relief and Reconciliation in the Middle East were now having to think extremely cautiously about where to send people: "As an organisation working in Iraq with staff on the ground we now have to consider much more carefully where we operate, when we go to places, how we get to places in the north of Iraq.
"There's umpteen different militias and forces controlling different checkpoints. There are many Shia militias, there are Iraqi forces, there is the Kurdistan forces, the Peshmerga. It's so complex, the number of different checkpoints that there are in the north of the country, and traveling from A to B is quite an issue. You have to do a risk assessment up to the minute as to whether you can go. It's become so difficult to have any confidence about where is safe to be."
President Hassan Rouhani, left, meets family of Iranian Revolutionary Guard Gen. Qassem Soleimani, who was killed in the U.S. airstrike in Iraq, at his home in Tehran, Iran, Saturday, Jan. 4, 2020. (Iranian Presidency Office via AP)
"We would therefore encourage people to pray fervently for the people of Iraq, all the people of Iran, obviously, our focus is particularly on the vulnerable minorities, the Christians, the Yazidis and others. Pray for them, pray for their safety, pray for political leaders in Iraq, because there are people who can be peacemakers.
"Most of the people in Iraq just want to live in peace, like anywhere else in the world. So pray for those political leaders and be in contact, if you're able to, with our own political representatives to say what you feel about this, to encourage them to support our government to be a positive influence in this situation"