US Secretary of State Mike Pompeo has made an unannounced visit to Iraq.

Pompeo cancelled a trip to Germany on Tuesday to fly to Baghdad. He told reporters that he was making the visit because of indications that Iranians were "escalating their activity" and intelligence about "imminent" plans for attacks.

He refused to give further details, but US media reports say Iran has likely moved short-range ballistic missiles to ships in the Persian Gulf that could target US troops and those of US allies.

Pompeo reportedly asked Prime Minister Adel Abdul Mahdi and President Barham Salih to ensure the safety of Americans in Iraq and reaffirmed that the US would cooperate to defend the country.

Pompeo's trip follows the expedited deployment by the United States of the aircraft carrier USS Abraham Lincoln's strike group and B-52 bombers to the Middle East.

NHK