WASHINGTON—Treasury Secretary Steven Mnuchin said he is sensitive to concerns about rising federal debt but emphasized that low interest rates and the urgency of helping the economy during the coronavirus outbreak cut in the other direction.

“This is a war, and we need to win this war and we need to spend what it takes to win the war,” he said Wednesday morning on Fox Business. “We are sensitive to the economic impacts of putting on debt and that’s something that the president is reviewing with us very carefully.”

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