On Monday, 7 June, Met detectives witnessed a man meet two other men in Upney Lane, IG11, and remove a number of boxes from their vehicle into his own car.
Officers approached and detained the man, aged 66, before carrying out a search under Section 23 of the Misuse of Drugs Act.
Inside the car, a number of boxes were recovered. These contained a total of 96kg of white powder, suspected to be Ketamine, a Class B controlled drug with an estimated street value of £3,840,000.
He was arrested on suspicion of possession with intent to supply controlled drugs.
Two men in their 30s, who were seen removing the boxes from their vehicle, were also arrested for drugs offences.
All three remain in custody at a north London police station.