Donald Trump has defended the killing of a senior Iranian military commander in an attack at Baghdad's International Airport.
The US President claims Qassim Soleimani was planning to kill Americans.
Seven people in total died in the airstrike.
The UK is among several countries urging the US and Iran to remain calm, after the Iranian defence minister promised a "crushing revenge".
In a statement, Foreign Secretary Dominic Raab said: "Following his death, we urge all parties to de-escalate. Further conflict is in none of our interests."
While attention turns to how Iran might retaliate, international lawyer and church consultant on Middle East issues Dr Harry Hagopian warned at the potential for rapid escalation of tension.
"If the Iranians attack, would then President Trump feel bound to attack again?" he said. "Testosterone levels run very high in both countries - both in the White House and in Tehran."
Urging prayer for the situation, he said: "The region is erratic...what we need to do is pray for wisdom to keep people from going astray and realise there is more than just one or two people involved - a whole region could go up in flames."
Listen to Dr Harry Hagopian speaking to Premier's Tola Mbakwe: