India, March 2 -- The United States has issued its highest travel warning, "Level 4: Do Not Travel" for Iran and Iraq, as tensions rise following US combat operations in Iran.

In a February 28 "Worldwide Caution," the US Department of State said: "Following the launch of US combat operations in Iran, Americans worldwide and especially in the Middle East should follow the guidance in the latest security alerts issued by the nearest US embassy or consulate." The department added: "The Department of State advises Americans worldwide to exercise increased caution."

Level 4 is the most severe advisory issued by the State Department and instructs Americans not to travel to a country "for any reason."

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