Britain's top commander in Iraq and Syria has warned foreign fighters travelling to join Islamic State (IS) in the region: "We will target you, we will find you, and we will kill you."
Major General Rupert Jones said it did not matter where people came from, as they would all be treated the same.
Speaking to the Press Association, he said: "If you come to Iraq, if you come to Syria, and you bear arms against the people of Iraq and the people of Syria, against the sovereign forces of this country in Iraq, we will target you.
"It does not matter where you are from, we will target you under the laws of armed conflict, and it does not matter whether you come from London or Rome, we will target you, we will find you, and we will kill you."
The deputy commander of the international anti-IS coalition shared similar sentiments about the leader of the "evil organisation", Abu Bakr al-Baghdadi.
Gen Jones said: "If we knew where he was hiding, his life would not last long.
"The point that is important is that the vast majority of his loyal lieutenants are already in graves.
"He and what is left of his leadership structure is in hiding. They are skulking and they are hiding for their lives.
"I am reasonably confident that he will be found, and when he is found, it will not be a pretty end for him."
He added that by hiding, al-Baghdadi was not demonstrating credible leadership, and had deserted IS fighters in Mosul and across the region.
Mosul, with a population of 1.5 million, has been an IS - also known as Daesh - stronghold for two-and-a-half years, but coalition forces are edging closer to recapturing it.
Gen Jones said: "Once Mosul has been liberated, there is an inevitability to Daesh's defeat in Iraq. They will have lost their so-called capital in Iraq.
"For us as a coalition, we are also defeating Daesh in Syria. All eyes at the moment are on Raqqa - the self-proclaimed capital of what they like to call the caliphate.
"Raqqa is increasingly isolated, both physically and morally. We would expect the attack into Raqqa to start at some point over the coming weeks."
He explained that an exact date for this had not yet been set, but said of Mosul: "Mosul is going to be liberated. It is completely isolated, but exactly when PM Haider al-Abadi will be in a position to declare it fully liberated, we will see."
The international coalition's mission is to defeat Daesh in Iraq and Syria so that the people of those countries can be liberated. British troops are not involved in a combat mission, and are helping to train Iraqi security forces.
"I am very confident that Daesh will be defeated," said Gen Jones.
"Will there be some kind of follow on capability? Yeah, sure. Daesh have demonstrated time and again their ability to adapt and to learn.
"Daesh fighters are highly determined fighters and we should assume that they will adjust and that they will try and continue to spread their message of hatred within Iraq and elsewhere."
On March 13 Royal Air Force Typhoons provided close air support to Iraqi troops engaged in intensive street fighting against IS extremists inside Mosul.
Armed with Paveway IV guided bombs, they first conducted an attack north-west of the city on a terrorist supply route, then carried out strikes which destroyed six IS defensive positions in western Mosul.
Despite cloud cover, each of the six targets was destroyed by a direct hit, and the Iraqi forces confirmed the threat each had posed had been eliminated.
Two days later Iraqi troops in west Mosul reported encountering a former school compound and two neighbouring buildings which a large number of Daesh fighters now occupied, armed with light machine-guns and rocket-propelled grenades.
Two Tornados attacked after dark - having conducted careful checks for any sign of civilians in the area - and hit the Daesh positions with three Paveway IVs, which destroyed the terrorist firing points.
Gen Jones said: "What we are here to do is to help our partners, Iraqi security forces and then we have vetted opposition partners in Syria, to defeat an evil enemy who has no humanity.
"And we see that day in day out, in all of the towns and cities that Daesh control.
"Seeing what Daesh do to innocent people, that has no humanity. What we are here to do is to clear the enemy so that people can live their lives again."
Asked if he has been surprised by anything he had seen, he added: "Yes and no. Nothing surprises me about Daesh. They are capable of anything - we have all seen that.
"Equally, the day when you wake up and can normalise what they are doing in your own mind, is a bad day.
"So one should always be shocked by their actions. We should never wake up one morning and go 'oh look, it's another beheading', or 'oh look they've just executed more people', that should always be shocking. But regrettably there is no surprise in it."