The United States has reportedly applied to seize an Iranian supertanker detained by the Royal Navy off Gibraltar last month.
The Gibraltar Chronicle claims the development led to a last minute application by the US Department of Justice to extend the detention of the ship, which it said British officials were planning to release.
The Justice Department is yet to comment on the report.
The Grace 1 was seized last month in a Royal Navy operation amid suspicion it was violating European Union sanctions on oil shipments to Syria.
Its seizure deepened international tensions in the Persian Gulf.
The Gibraltar government says it has been seeking to “de-escalate” the situation over the Grace 1.