(CNN) Washington Gov. Jay Inslee dropped 12 years of tax returns Friday morning on his campaign website and challenged President Donald Trump during his "favorite" morning show to do the same.

"Today I am challenging Trump on his favorite show to release his tax returns like I did this morning," the Democratic presidential candidate said Friday on "Fox & Friends."

"It is time for him to come clean with the American people," Inslee argued on a morning show that the President regularly tunes in to watch. "He's got to show what he's been hiding and Americans deserve that truth."

Inslee is the latest Democratic presidential candidate to release his tax returns in what could be a litmus test for the 2020 hopefuls. The Washington governor had previously released his 2007 to 2015 tax returns during his gubernatorial campaign and reelection bid.

New York Sen. Kirsten Gillibrand became the first 2020 presidential candidate on Wednesday to disclose her 2018 tax return, along with her past tax returns dating back to 2007.

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