Greenhalgh was found guilty in June of ten offences covering the illicit supply of S‑125 Pechora missile systems, AK‑47 rifles, battle tanks and hundreds of thousands of rounds of ammunition between 2009 and 2016.
Greek national Christos Farmakis, 48, was convicted of nine similar offences; he was tried in absentia and his whereabouts remain unknown.
Judge Sally‑Ann Hales imposed identical 16‑year sentences on both men, noting that they repeatedly sought to breach UK arms‑export bans in pursuit of substantial profit.
Prosecutors said the only charge involving an actual transfer was the sale of a former Ukrainian S‑125 missile system to South Sudan, a region that remained under a British arms embargo until its independence in 2011.
The pair also arranged to supply fighter jets to Libya during its civil war and were accused of planning arms shipments to Iran, Iraq and Syria, all in violation of international embargoes.
Farmakis was apprehended in 2016 after investigators traced an email sent from his official Greater London Enterprise account to his superiors, which led to the discovery of documents outlining the proposed deals.
The convictions highlight the UK’s determination to enforce its export‑control regime and send a warning to illicit arms networks operating across conflict zones.