Former MI6 chief Sir Richard Dearlove has sharply criticized Green Party leader Zack Polanski over his positions on UK defence and foreign policy, calling him “really dangerous” and accusing him of holding what he described as an “absurd” view of geopolitics.
In a video shared on X by Defence On The Brink, Dearlove who led Britain’s Secret Intelligence Service from 1999 to 2004 said he was alarmed by Polanski’s past comments suggesting the UK should leave NATO and reconsider its nuclear deterrent. According to Dearlove, such positions place the Green leader “off the map” when it comes to serious strategic thinking.
He also said he “intensely disliked” the Green Party’s campaign strategy in the recent Gorton and Denton by-election, claiming it appeared aimed at consolidating the Muslim vote. The by-election, triggered by the resignation of Labour MP Andrew Gwynne on health grounds, resulted in a surprise Green victory. Hannah Spencer, a 34-year-old plumber, won the seat, with Reform UK finishing second and Labour third a significant upset in what had previously been considered a safe Labour constituency.
Prime Minister Keir Starmer described the outcome as “very disappointing” for Labour.
The Greens campaigned on messages including “Stop Islamophobia” and “Stop Reform,” and the result represented a 27.5% swing from Labour to the Green Party. Polanski celebrated the win as a sign of momentum, saying that if a similar swing were repeated at a general election, it could lead to a “tidal wave” of new Green MPs.
Dearlove’s criticism extended beyond NATO. He mocked Polanski’s reported suggestion of exploring alternative alliances, including potential cooperation with countries such as Brazil and Mexico. Laughing during the interview, Dearlove said he was shocked that such proposals were gaining traction, even while acknowledging that the Greens remain far from forming a government.
🚨Ex-MI6 Chief Sir Richard Dearlove says Zack Polanski is a threat to Britain's defence and national security.
"This man is really dangerous, making crazy statements about NATO. He's come out with some weird idea about a military alliance with Brazil and Mexico." pic.twitter.com/XjKtYn4ctG
However, he warned that a broader far-left coalition involving the Greens and other parties could pose risks to what he views as the UK’s national security framework. He said he found it puzzling that Polanski whom he described as having a “very strange political past” was gaining wider attention.
Earlier this year, Polanski reignited debate by arguing that Britain’s reliance on the United States particularly under a potential Trump presidency creates strategic vulnerability. He suggested the UK should expel US forces from British bases and instead pursue a more Europe-focused defence arrangement. He has framed this approach as a move toward greater strategic independence rather than isolationism.
Before entering frontline politics, Polanski worked as an actor and hypnotherapist. He was initially active in the Liberal Democrats, standing as a council candidate in 2016, before joining the Green Party in 2017. He has said the party’s stance on refugee rights influenced his decision. Polanski served as Deputy Leader from 2022 to 2025 and sits on the London Assembly. In September 2025, he was elected Green Party leader with 85% of the membership vote.
Born David Paulden, he adopted the surname Polanski a family name at 18, and chose the name Zack inspired by a character from the novel Goodnight Mister Tom. He is openly gay and vegan.
The debate over his defence policies highlights a broader national conversation about Britain’s role in NATO, its nuclear deterrent, and the future direction of UK foreign policy in an increasingly uncertain geopolitical landscape.
