Rubio will meet with officials in Reykjavik "to discuss economic and security collaboration," the US State Department said in a statement announcing the trip.
The lightning visit, as symbolic as it is political, comes after the US signed a security pact with Denmark and Greenland in late September on the sidelines of the United Nations General Assembly in New York.
The agreement has apparently put an end to President Donald Trump's threats to buy or even annex Greenland, which soured relations with the EU.
Under the pact, Washington plans to establish two new military bases on Greenland, drawing the autonomous Danish territory further into US orbit.
With competition on the rise in the Arctic, Iceland has regained status as a strategic player, even as the island continues to rely heavily on the United States for security.
At the start of September, Trump sparked new controversy by sharing an AI-generated map that appeared to show all of North America, the Caribbean, Greenland and Iceland as "the United States of America."
In response, Reykjavic summoned the US ambassador "to convey a clear message that the image was wholly inappropriate," Iceland's foreign ministry said in a statement to AFP.
Icelanders had voted in late August 52.8 percent to 47.2 percent against resuming negotiations on joining the European Union, which have been frozen since 2013.
The last US secretary of state to visit Iceland was Antony Blinken in 2021.
Since gaining independence in 1944, Iceland has never had a military. It relies on the North Atlantic Treaty Organization (NATO) for its security and on a bilateral defense pact signed with the United States in 1951.
Washington does not have a permanent base in Iceland, but is looking to consolidate its control over Arctic access routes coveted by Russia and China.
Trump again signaled his obsession with Greenland on Sunday, posting on his Truth Social platform an AI-generated image of his face looming over what appears to be its landscape, accompanied by the words "Hello, Greenland!"
Greece, Portugal
After Iceland, Rubio continues to Athens to participate in a "strategic dialogue" with NATO member Greece on regional and energy security, the State Department said.
The wars in Iran and Ukraine have laid bare the fragility of energy supply chains, and Greece is positioning itself to become a key hub in southeastern Europe for natural gas transport.
The visit follows media reports about possible conflicts of interest involving the US ambassador to Greece, Kimberly Guilfoyle, a former fiancee of Donald Trump Jr. and ex-wife of California Governor Gavin Newsom.
In a letter addressed to Rubio, Congressman Gregory Meeks sought clarification of a Wall Street Journal report alleging she had stated the United States could create "political change" in European countries.
Rubio later wraps up his European tour with a brief stop in Lisbon.



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