Secretary of State Marco Rubio said a "foreign actor" was involved in the terror plot that killed two people in the United Kingdom, confirming U.S. intelligence has linked the attack to forces outside Britain.
Rubio made the remarks during a press appearance Saturday, according to reports from Google News. He did not name the country or group behind the plot, citing the ongoing investigation.
British police have arrested multiple suspects in connection with the attack. Authorities have not publicly identified the victims or released a full account of how the plot unfolded.
The confirmation of foreign involvement raises the stakes for a case that already spans two continents. It suggests the attack was not carried out by a lone actor operating without outside direction.
Rubio's statement marks the first time a senior U.S. official has publicly tied a foreign government or organization to the plot. Washington and London have shared intelligence on counterterrorism cases for decades, and the U.S. routinely provides technical support to British investigations.
The secretary's comments came as UK officials continued their own inquiry. British counterterrorism units have not confirmed whether they are pursuing suspects beyond those already in custody.
Foreign involvement in a UK terror attack would trigger diplomatic consequences. Depending on which actor is identified, the British government could expel diplomats, impose sanctions, or invoke NATO consultation provisions.
Rubio did not say whether the U.S. would take retaliatory action or whether the foreign actor was a state or a non-state group. Those distinctions matter: state sponsorship typically produces a stronger diplomatic response than support for a proxy organization.
The attack has drawn attention from lawmakers on both sides of the Atlantic. U.S. officials have not said whether American citizens were among the victims or targets.
Investigators have not released a timeline for when charges might be filed. British police can hold terror suspects without charge for up to 14 days under existing law.
The State Department did not immediately respond to questions about which foreign actor Rubio was referencing. The UK Home Office declined to comment on his remarks.
Rubio's confirmation adds pressure on the UK to disclose what it knows. The two allies now face questions about whether the plot could have been detected earlier and what warning signs intelligence agencies may have missed.
