The head of MI6 has accused Russia of trying to turn the Syrian city of Aleppo into a desert… and then 'call it peace'.

Alex Younger, who's known as C, was giving his first public speech in the role, and the first ever speech at MI6 headquarters in London.

He warned Russia's actions would have a 'tragic' outcome, which could increase the threat to Britain.

Mr Younger told an invited audience of around 30 journalists that the scale of the terrorist threat facing the UK is unprecedented.

He spoke of "highly-organised" external attack planning structures in the IS terror group, Daesh.

Even as they face military threat he says they are plotting ways to project violence against the UK and our allies without ever having to leave Syria.

In the fight against international terrorism, he said legitimacy was one of MI6's most important weapons.

That was followed by a warning to Russia and Syria, whose actions he clearly thinks lack legitimacy. Mr Younger said:

"In defining as a terrorist anyone who opposes a brutal government, they alienate precisely the group that has to be on side if the extremists are to be defeated."

"Meanwhile, in Aleppo, Russia and the Syrian regime seek to make a desert and call it peace. The human tragedy is heartbreaking."

But his real worry is that those Syrians who have rejected both the government and Daesh will become radicalised as a result of Russia and President Assad's actions.

Groups like Jabat Fateh al-Sham could grow into a bigger threat to be faced alongside Daesh, and even after its defeat.

A threat not just in the Middle East – but to Britain and its Western allies.

In reality, there were no great surprises in Mr Younger's speech. He seemed on a mission to highlight the importance of the work done by his agents and officers, and to build public support for that.

But he acknowledged by its very nature MI6, officially known as the Secret Intelligence Service, cannot be terribly transparent.

The most surprising thing was that such a large group of journalists, people whose jobs are to root out secrets, were invited into the Vauxhall Cross HQ for the first time.

MI6 Chiefs have made public speeches before, but the decision to do it at the heart of the organisation is a symbolic one; an attempt to show a drive for as much openness as possible.

It is an iconic building from the recent James Bond film, but we got to see very little of it; a garage, a central hallway with a Christmas tree, and a small lecture theatre.

Some of the gathered journalists felt it ended up seeming more cloaked, and less open, than previous speeches.

But Alex Younger wanted to make a statement, to draw attention to his belief that MI6 is active and effective on behalf of the country – and by inviting journalists into MI6 he did at least get our attention.

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