US Secretary of State Marco Rubio has arrived in Reykjavik, Iceland, on the first leg of a four-day European tour that will also take him to Greece and Portugal.
According to a State Department announcement, the top item in Rubio's talks with Icelandic officials on Monday is "economic and security cooperation."
Before departing, Rubio told reporters he would not directly link the decision to withdraw US B-1 bombers from Britain's Fairford base to the incident that occurred there last week.
"I wouldn't directly connect that to the action that was taken," Rubio told reporters, adding that "the Department of War is constantly reallocating resources to where they are needed."
The secretary of state said he was confident in the security of all US bases and praised the cooperation of UK authorities.
Five British men were arrested near the UK's Fairford air base on suspicion of preparing "terrorist acts" and were later released on bail. A sixth man, holding dual British-Iranian citizenship, was arrested separately in London and has also been released on bail.
The B-1 bombers have been sent back to the United States. They had previously been used for airstrikes targeting Iran.
However, a NATO military source said: "There remains an assessment that Iran poses a serious threat to US assets in the UK."
Iran's Islamic Revolutionary Guard Corps had earlier described Fairford base as a legitimate target, but Tehran denies any connection to last week's incident.
Rubio will also travel to Greece to lead the US delegation at the sixth US-Greece Strategic Dialogue, focused on defense cooperation as well as regional security and energy, and will conclude his tour in Lisbon, where he will discuss defense, economic and technological cooperation.
