The arrest of the former head of Germany’s spy agency has shone a spotlight on the close links he shared with Britain – raising concerns about the possibility that intelligence from agencies including MI6 may have been compromised.

August Hanning, who led Germany’s Federal Intelligence Service (BND) from 1998 to 2005, is accused of illegally collecting thousands of classified documents and using them in analysis for a foreign spy service.

Experts in the UK have described “friendly” meetings with Hanning, 80, who now stands accused of what could be Europe’s most serious security breach since the Cold War.

But British former intelligence chiefs said heightened unease over the possibility of leaks, and of pro-Russian sympathies within the BND in the past, meant information-sharing was more carefully controlled than with other allies.

Sir Francis Richards, head of intelligence agency GCHQ from 1998 to 2003 when Hanning was his opposite number in the BND, said they did not have “a terribly close relationship”.

He told The i Paper. “Our relations with the Germans at that stage were nowhere near as close as with the French or the others, particularly the Americans.”

He had not had specific concerns about Hanning, he added, but “given the complexities of German domestic politics and their rather nuanced relationship with the past with Russia in particular, it was just not a terribly, terribly close relationship”.

No trust ‘in a month of Sundays’

Sir Richard Dearlove, the former head of the MI6, warned in a 2024 interview with that he was highly selective about what intelligence he shared with the BND over fears it would leak to Russia. In that same interview, Hanning was described as a “personal friend” of Dearlove.

Richards said he “would agree” with the former MI6 chief that he would not have passed some sensitive material to the Germans “in a month of Sundays”.

He recalled a “friendly first meeting” with Hanning at which he suggested “some ways in which we might co-operate”, but added: “The next time I met him, he seemed to have gone cool on all of that.”

While the German’s arrest would be a “worry” for British intelligence services, Richards doubted whether the identities of MI6  officers or agents would be in jeopardy.

The relationship with the BND was not as close as with the “Five Eyes” intelligence-sharing alliance of Australia, Canada, New Zealand, the UK and the US, he added.

“’The quality and our relationship with the Germans, in terms of the amount of information we exchanged with them, was never that great,” Richards said. “It was a transactional relationship. And when we could be useful to each other and could do so without risk to ourselves, then we would certainly consider it.”

Writing for The i Paper, foreign affairs expert John Kampfner, who is based in Berlin, also knew Hanning, having first met him in 2019. He last saw him less than a month ago at a reception at the British Embassy in Berlin for a German-British-French group whose steering committee Hanning happened to be on.

Wariness over ties to Russia

Anthony Glees, an intelligence expert specialising in British-German relations, also met Hanning, this time at a conference in Berlin after he left the interior ministry in 2009.

“The fear about the Germans being leaky not only came from the fact that Germany had been divided between East and West until 1990, but that after 1990, people were pulled into the BND who had been part of the East German intelligence apparatus,” he said.

There had been concerns about infiltration of the BND by the Stasi after German unification, he said, describing the former East German secret police and Russia’s KGB as “two sides of the same coin”

“Hanning, being in charge from 1998 to 2005, was in prime pole position to oversee all of this,” added, Glees, who is also an professor of politics at the University of Buckingham.

Vladimir Putin worked as a KGB spy in former East Germany in the 1980s and held a Stasi ID pass, which was discovered in 2018 during research into the close co-operation between the East German intelligence service and the KGB.

Putin was in Dresden until December 1989 after the fall of the Berlin Wall, when the communist East German regime collapsed. In 1990, senior West German counterintelligence official Klaus Kuron was ​exposed as a Stasi spy and later convicted of treason.

Germany’s close political ties to Russia continued for far longer. For three decades following the Cold War, successive German governments believed in soft power and deepening economic interdependence and trade with Russia. Foreign policy was focused on Wandel durch Handel (change through trade), which resulted in Germany’s heavy reliance on cheap Russian gas via the Nord Stream pipeline.

This policy collapsed into a state of hostility following Russia’s invasion of Ukraine in 2022 and the sabotage of Nord Stream, when a series of underwater explosions and consequent gas leaks rendered three of the four pipes inoperable.

What was Hanning involved in?

While Hanning would have come into contact with his opposite number at MI6, Glees said it was unlikely the German would have had direct access to then prime minister Tony Blair while at the BND.

After leaving the spy agency, Hanning held the role of state secretary at Germany’s interior ministry until 2009. He has since been working as a private consultant.

Counter-terrorism, and the 2006 murder of former KGB spy Alexander Litvinenko in London, are among topics he would have been likely to discuss with his opposite numbers in the British government during his time at the interior ministry, Glees said.

This position “would have kept him in the intelligence game,” he added. “I think one could say that Hanning was ‘active’ until 2009.”

Hanning was in charge of the German secret service when a defector’s lies about weapons of mass destruction were used by the US to justify the 2003 invasion of Iraq.

The BND handled an Iraqi informant, codenamed Curveball, who claimed Saddam Hussein had biological weapons laboratories. In a 2002 letter to the CIA chief, Hanning said Curveball’s claims were “plausible and believable” but not verified. But the informant’s fabrications were relied on by both the US government and the UK in the decision to go to war with Iraq.

The allegation: Espionage for a foreign power

Hanning was arrested on Tuesday on suspicion of espionage, treason and obtaining classified information for a foreign power,

Prosecutors allege he used classified intelligence to “draft an analysis” for one foreign intelligence service, and maintained contact with another foreign spying service.

A former aide of Hanning, Manfred D, is accused of aiding and abetting attempted treason and treasonous espionage by providing his former boss with around 2,000 documents over a 12-year period until 2022.

Prosecutors did not reveal who the two men were suspected of spying for, but German newspaper  reported that Hanning was said to have prepared an analysis for Azerbaijan’s intelligence services.

The German federal prosecutor’s office said it had not yet been possible to determine whether the report had reached its intended recipient.