LONDON: A keen mountaineer with a military background, Britain's new spy chief faces the daunting mission of rescuing the dented reputation of MI6 while combating jihadist threats and facing down the menace of a new confrontation with Russia.

Alex Younger — or “C” as the heads of foreign intelligence agency are codenamed — was appointed this month to preside over the imposing MI6 headquarters on London's River Thames, its stepped-block shape earning it comparisons to a Sumerian ziggurat temple.

Something of a secret in plain sight — special effects saw it blown up in the most recent James Bond film, “Skyfall” — the fortress is listed on maps as a mere “government building”.

As Younger's predecessor John Sawers once said, “secret organisations need to stay secret”.

As a career spy and MI6 insider, the 51-year-old Younger, an economics graduate and former army officer, knows the territory inside out. He has been with Britain's spy agency — properly known to its employees as the Secret Intelligence Service — since 1991.

Younger rose through the ranks to become the head of intelligence operations worldwide for the past two years, according to a brief biography released by the Foreign Office.

In the past he has worked in Europe, the Middle East and Afghanistan, and directed MI6 operations to protect the London Olympics in 2012.

“Alex brings a wealth of relevant experience,” Foreign Secretary Philip Hammond said on Younger's appointment.

Iraq fiasco

Described as a “cool customer” who is “popular with his colleagues,” according to a former senior MI6 officer who spoke to The Daily Telegraph newspaper, Younger is said to have a forthright approach that won him the job over two other candidates.

His task will be to continue the work of the outgoing Sawers, who over the last five years worked to restore the reputation of the service after accusations of complicity in torture, mass surveillance and false claims about Iraq possessing weapons of mass destruction (WMD).

In 2002, then-prime minister Tony Blair used a discredited document dubbed the “September Dossier” to justify the invasion of Iraq, which claimed dictator Saddam Hussein could deploy WMDs “within 45 minutes”.

“MI6's reputation was damaged by the WMD fiasco,” Stephen Dorril, an intelligence expert at the University of Huddersfield, told AFP.

Over the past year, “in what seems to be a deliberate public relations approach,” former senior MI6 staff have appeared at conferences and in the media giving nuanced views of the so-called “War on Terror”, Dorril said.

It is a turnaround for an organisation which was not officially acknowledged by the British government until 1994.

“I think this is maybe to distance the service from any form of politicisation and pressure from government, but also to publicly improve the image of the service,” Dorril added. It is no small task.

As he takes the reins of MI6, Younger must take on his predecessor's challenges — including Iraq, Syria, and Ukraine — 10 weeks after Britain's terror alert was raised to “severe” in the face of risks from jihadist groups.

A resurgent Russia, whose actions over Ukraine and stepped-up militarisation recall Cold War schemes, could also be problematic.

In his new post, Younger will take on the single-initial nickname “C “(famously changed to “M” in the Bond series, and referred to as “Control” in John Le Carre's spy novels).

That initial was used by the first director of the Secret Intelligence Service, George Mansfield Smith-Cumming, to sign off on documents a century ago, and was adopted to refer to MI6 chiefs ever since.