WASHINGTON—President Trump said he plans to sign an executive order temporarily suspending immigration into the U.S., saying he was doing so to protect American jobs as the novel coronavirus has taken a sharp toll on the economy.

In a tweet Monday night, he said he was signing the executive order “in light of the attack from the Invisible Enemy”—a reference to the coronavirus—“as well as the need to protect the jobs of our GREAT American Citizens.” He didn’t provide further details.

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