Trump tweeted that it "should have been reported as a positive, not a negative."
He also suggested that when the term "executive time" appears on his schedule, it means he is "generally working, not relaxing."
The president's work ethic has been a topic of Washington conversation after Axios obtained three months of his private schedules.
They revealed that he spent 60 percent of his time in executive time, a term coined by former chief of staff John Kelly for unstructured time in Trump's day. That time often coincides with when Trump is on Twitter.
Acting chief of staff Mick Mulvaney said the leaker's identity should be known this week.
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