Hillary Clinton went on a Twitter tirade Wednesday against Donald Trump, asking the billionaire 20 questions about reported conflicts of interest that he may have if elected.

The Democratic presidential nominee was referencing a Newsweek cover story arguing that the Trump Organization’s international business relationships could make it hard for a President Trump to conduct foreign policy.

In a post on her website, Clinton said that Trump’s career was “full of sketchy relationships with foreign countries.”

The posts comes amid a debate over Trump’s tax returns, which he has declined to make public, citing a pending IRS audit as prohibiting him from releasing his taxes.

In her tweets, Clinton questioned what Trump would make a priority—America or his personal investments.

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