A warrant of further detention was granted at Westminster Magistrates' Court on Wednesday, allowing the two men to be held until 27 October. Both were re-arrested on Tuesday on suspicion of assisting a foreign intelligence service under Section 3 of the National Security Act 2023.
The suspects, a 24-year-old UK national and a 25-year-old dual UK-Iranian national, both from the borough of Westminster in London, were initially arrested in September and October. The 24-year-old was first detained near the Gloucestershire RAF base on 27 September, while the 25-year-old was arrested in Westminster on 1 October.
Five other men arrested as part of the probe remain on police bail.
CTP has said it is "highly likely that there is Iranian state involvement" in the incident. RAF Fairford has been used in recent months by US bombers for strikes against Tehran during the Middle East war, after then-prime minister Sir Keir Starmer granted Washington permission to use British bases for "defensive" strikes. The US Air Force withdrew all of its bombers from RAF Fairford earlier this month following the suspected plot.
Assistant Commissioner Laurence Taylor, head of National Counter Terrorism Policing, said: "This is very much a live investigation, and our evidence gathering continues, but at this time our position remains the same; we consider it highly likely that there is Iranian state involvement. Our investigators are continuing to examine what that level of involvement was and the ambition behind it."
Taylor added that specialist teams had been "working tirelessly to interrogate the many lines of enquiry" and that national security investigations "can take time to progress".