Heightened alert to Iranian terrorism is very much warranted. The reality is that Iran’s state sponsored terror cells are ALREADY operating in plain sight on Britain’s streets. And I’m afraid to say it but Britain’s softness and naivety have made it easy for them. There is absolutely no doubt there are operatives on Britain’s streets, as there are in Germany, Belgium, France and other European countries, just waiting for the go-ahead from Tehran. Britain cannot and must not wait for a catastrophe to happen.

We in Iran have tasted the blood lust of this regime. Be under no illusion, they are trying to bring the same thing to Europe and will if they are allowed. Britain and Europe are open, vulnerable, and seemingly in denial about the terrible nature of this regime – and its capabilities. Britain and Europe have become naive. They seem to think the Middle East is another country far away that can't affect the UK.

But make no mistake, these people will bring carnage to British streets in a heartbeat if they feel it serves their needs.

Britain's lack of security, the porous borders of Britain and Europe, are a running joke. Maybe a couple of times a year there will be an incident in a European country and I know there's an Iranian link.

If Britain doesn’t learn to root out the tree it will keep growing. If it doesn't contain the activities of Iran then something terrible will happen.

When people talk of “sleeper cells” it makes them sound like the well-organised organs of a super-power. But we must remember they are not unreachable.

It is really not the regime’s power or influence that is the reason they are here. It is simply because they have been given opportunities by western states who are sleepwalking to disaster. Britain has made it easy for them.

I am a member of Resistance Units, affiliated to the People’s Mojahedin Organization of Iran, the principal Iranian resistance movement.

I have been fighting Ayatollah Ali Khamenei and his terrible fascist theocracy all my life and know I am a marked man. I have seen how people, including my friends, have been picked up without warning by the Revolutionary Guard.

I have witnessed how young women and men are arrested, beaten up and know how some of them have sacrificed their lives fighting the tyranny ruling Iran.

But we, the people of Iran need, and are determined to spark our own regime change – to become a free and democratic fair country of the kind the 10-point plan of Maryam Rajavi, the President-elect of the National Council of Resistance of Iran, is advocating - one in which democracy reigns, genders are equal, religion and state are separate and we are nuclear-free.

All we need is for Britain and the West to recognise our right to resist and not to accept the dictatorship as a legitimate state with which we can negotiate.

Believe me, amid the horrors there is much hope. Everyone on the streets is ready and all it will take is a spark. We are working for it day in and day out, trying to make it happen.

There is this tension on the streets and we try to work with that, and work with the Resistance Units, to foment an uprising and a revolution.

Nobody is happy with violence but when we were on the streets in the 2017 uprising they were firing live rounds at us – they were shooting dead their own people.

What does the West want us to do, throw flowers at them? We are trying to show the rage of the people.

I live in fear of my life. This regime is violent and it kills people on a whim. And when it is cornered the killing gets worse.

But now there are negotiations and smiley faces from the West – it is incomprehensible. Many young people in Iran say Trump is buying the regime breathing space with negotiations – breathing space to finalise a nuclear weapon.

And when the regime gets a nuclear weapon, believe me, the negotiations will be over.

Saheed Tabrizi is not the author’s real name. It has been changed for his own safety in light of actions by Iran's Revolutionary Guard