Counter Terrorism Policing re-arrested the two men on Tuesday as part of the investigation into activity near RAF Fairford in Gloucestershire last month.
The 24-year-old UK national and 25-year-old dual UK and Iranian national, both from the borough of Westminster, London, were arrested on suspicion of assisting a foreign intelligence service.
Police added that it was "highly likely that there is Iranian state involvement" after three large vans were stopped near the airbase in the early hours of 27 September.
The 24-year-old man was initially arrested that day near RAF Fairford and the 25-year-old was later arrested on 1 October in Westminster, central London.
Five other UK nationals in their mid-20s were also arrested after the incident, all are still on police bail as the investigation continues.
Assistant commissioner Laurence Taylor, head of national counter terrorism policing in the UK, 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."
He added: "We know the public have unanswered questions. I want to be as transparent as possible and when we are in the position to share more, we will."
Three suspicious vans were stopped near the airbase in Gloucestershire on 27 September.
More from Sky News:
Antisemitism in English schools to be revealed
Zelenskyy meets with Trump envoy
Earlier this month, the US removed its bombers from RAF Fairford, partly because of a reported threat of a possible Iranian drone attack, American officials told Sky News' US partner network NBC.
US President Donald Trump later told reporters outside the White House that "threats" led to the decision to remove the US bombers, including B-1s, B-2s and B-52s.
However, a spokesperson for Prime Minister Andy Burnham insisted the RAF base remains secure after the US military withdrew its strategic bombers over their security concerns.
Unions, industry sources and campaigners opposed to the development anticipate Ms Fahnbulleh will make the long-awaited announcement in Aberdeen, ending almost two years of uncertainty over the project.
The Department of Energy Security and Net Zero declined to comment.
The fate of the Jackdaw field, located 150 miles east of Aberdeen, and the Rosebank oil field off Shetland, has been in doubt since approval granted by the previous Conservative government was overturned in the Scottish courts in January last year.
Last week the energy secretary told Sky News a decision on Jackdaw was "imminent" but a decision on Rosebank "would take a little longer".
Developers Adura, co-owned by Shell and Norwegian oil giant Equinor, say Jackdaw is capable of supplying up to 6% of UK gas demand, and the two oil and gas fields will support 3,500 jobs at peak construction and raise almost £4bn in taxes by 2034.
Shell says emissions from Jackdaw will not materially influence global climate change.
Opponents of the scheme, including Greenpeace and Uplift, who challenged the original approval in court, say further North Sea drilling will put the UK in breach of its climate commitments and do nothing to bring down consumer bills.
Natural gas extraction peaked at the turn of the century but the UK still sources around 45% of supply from the North Sea, and fuel extracted from Jackdaw will feed directly into the domestic network.
Bringing Jackdaw on stream is unlikely to have a significant impact on UK gas prices but it would displace imports that, in the case of liquified natural gas (LNG), come with a higher carbon footprint.
The fate of Jackdaw and Rosebank has crystallised debate over the future of the UK's North Sea fossil fuel resources and the pace of transition towards Net Zero and the government's target to decarbonise the electricity grid by 2030.
More from Sky News:
Neglect 'contributed to baby's death'
Suspect arrested over town hall fire
While Labour committed to ban new oil and gas licences in its election manifesto and Conservatives and Reform have called for unfettered exploitation of North Sea reserves, Prime Minister Andy Burnham has promised "a pragmatic approach".
The UK still relies on fossil fuels for three-quarters of its energy supply and will continue to use oil and gas for decades even as the energy transition continues.
Esta High died at Leeds General Infirmary in November 2023, days after she was taken into the A&E with a high temperature and vomiting.
Her parents Lynsey Carr and Leon High claimed doctors missed crucial opportunities to test for a bacterial infection and begin vital antibiotic treatment.
Ms Carr told an inquest at Wakefield Coroner's Court how their concerns were ignored until it was too late.
An inquest jury of five women and six men concluded on Tuesday that: "Esta died of natural causes which was contributed to by neglect.
"Had Esta received required care, based on the balance of probabilities, it would have probably saved or prolonged her life."
The jury said chances were missed as doctors stuck with a Covid diagnosis after she tested positive for coronavirus.
There was no dispute that the young girl's cause of death was streptococcus pneumoniae meningitis, the court heard.
Lawyers for Leeds Teaching Hospitals NHS Trust admitted during the inquest that there had been missed opportunities to diagnose the bacterial infection which causes meningitis and give Esta antibiotics.
Ms Carr told the jury how Esta was a "happy, healthy, smiling girl" before she became ill on 31 October 2023.
The family, from Leeds, was put in a side room at the hospital's children's assessment and treatment (CAT) unit, Ms Carr told the inquest.
She believed staff were more concerned with isolating Esta due to the risk of Covid than with listening to her and Mr High.
Ms Carr said she and Mr High refused doctors' advice to take Esta home as she had a temperature above 40C and would not stop vomiting.
She said her daughter developed a rash and her arm started shaking, which she feared was a seizure.
Mr High filmed Esta's arm movements and this was shown to the jury.
More from Sky News:
Britain's first storm of the season named
BBC announces details of cuts in bid to save £500m
Ms Carr told the jury "we were extremely worried" and "we kept asking for help", but "staff were rude and don't listen to our concerns".
She said Esta's time on the CAT unit was "15 hours that were filled with missed opportunities".
By late afternoon on 2 November, Esta was not responding and the jury heard how scans and other tests showed evidence of meningoencephalitis and streptococcus pneumoniae.
Esta was taken to intensive care and efforts were made to save her life, but Ms Carr said it was too late. The child died on 6 November.
Ms Carr told the jury: "In just five months, Esta touched the lives of everyone who met her."
She added: "Unfortunately, as our daughter had been left untreated for 55 hours, it was too late to save our darling girl."
Dr Elizabeth Garthwaite, chief medical officer at Leeds Teaching Hospitals NHS Trust, said: "We are deeply sorry that we failed Esta and her family, and offer our sincere and heartfelt condolences to Lynsey and Leon following the tragic death of their daughter."
Dr Garthwaite added: "We recognise that serious failures occurred in the care provided to Esta and that these failures had devastating consequences.
"We take the concerns raised by the coroner extremely seriously and will carefully consider the report's findings and recommendations.
"We are committed to responding openly and fully, and to taking any further action necessary to improve patient safety."
Alisha Samuels, 26, was found with serious stab wounds by officers who were called to reports of a "disturbance" in Dorking Avenue at around 2am on Thursday.
She was pronounced dead at the scene, Greater Manchester Police said.
Lawrence Johnson was charged with murder and attempted murder on Tuesday.
He has been remanded in custody and is due to appear at Manchester Magistrates Court on Wednesday.
More from Sky News:
Jackdaw gas field to be approved
Should UK drill in the North Sea?
Police said the charges relate to the death of Ms Samuels and the attempted murder of a man in Dorking Avenue on Thursday.
A 25-year-old man was previously arrested, but police said on Friday he is "no longer being treated as a suspect for murder".
He has since been released on police bail.
Detective Chief Inspector Justin Bryant said: "We are continuing to work into establishing the full circumstances of Alisha's tragic death and to provide Alisha's family with some answers.
"We have now charged a man, but our investigation is not over.
"I urge others who may have information, no matter how small, to please come forward."
Officers were called to Orient Beach in KuGompo city, formerly East London, at around 7am local time (8am UK time) on Tuesday, where they found the woman's body, a police spokesperson said.
The woman was swimming with a group when she signalled for help, a witness told public broadcaster SABC.
"We all realised she'd been bitten by a shark, and she was in a very bad way," the witness said. "The bites were very severe, but there were only two, one on her thigh and one on her upper arm."
He said the woman was brought back to shore, where she was pronounced dead.
Officers who attended the scene found her body with open wounds, police said.
The species of shark involved in the attack was not immediately known.
An inquest has been opened into the woman's death.
More from Sky News:
Suspect arrested in France after fire at historic city hall
Police charge man after Australian MP struck by car
Fellow swimmer Mike Loewe described the victim as a recently retired nuclear radiographer and a musician, and said her death had devastated the swimming community.
"The Buffalo City Metropolitan Municipality is deeply saddened to confirm that a fatal shark attack occurred at the Orient Beach this morning, resulting in the tragic loss of a swimmer," municipal spokesman Luzuko Buku said in a statement.
Orient Beach and nearby Eastern Beach have been closed until further notice, and the municipality urged beachgoers to exercise caution.
South Africa's coast is popularly known for great white sharks, which draw tourists from around the world for cage diving, but shark attacks are rare.
The Florida Museum of Natural History's International Shark Attack File recorded 29 unprovoked bites in the country between 2012 and 2021, with six of those fatal.