Two US Air Force planes landed at RAF Fairford airbase in Gloucestershire, United Kingdom, on Sunday, according to The Guardian.
Footage reviewed by the Guardian showed two Boeing C-17 Globemaster transport planes landing at the airbase.
This comes after a US B-1 Lancer bomber arrived on Friday evening at RAF Fairford airbase.
Britain's Defence Ministry declined to comment on the issue, according to the Guardian, which noted that it was not confirmed whether the aircraft are ultimately headed to the Middle East.
Trump: 'Will remember' lack of British support in Iran war
US President Donald Trump said on Saturday that Britain is giving "serious thought" to sending two aircraft carriers to the Middle East, but added that the US does not need them to win the war with Iran, in the latest clash between the military allies.
Trump has repeatedly criticized British Prime Minister Keir Starmer, suggesting this week that he helped "ruin" the countries' historically close relationship after London blocked the US's initial use of British bases to attack Iran.
In a post on Truth Social, Trump said he "will remember" the lack of British support during the conflict with Iran.
The social media post comes after the British Defence Ministry said on Saturday that it was preparing the Prince of Wales aircraft carrier for possible deployment.
However, no final decision has been taken about whether to deploy the aircraft carrier to the Middle East, a British official said.
Starmer defends decision to block US from British bases
Starmer has defended his decision not to allow US forces to use British bases to support initial strikes on Iran, saying he needed to be satisfied that any military action was legal and well planned.
He later granted US forces permission to use British bases for what he called defensive strikes against Iranian missiles in storage depots or launchers.
Reuters contributed to this report.