New York (CNN) A New York appeals court has denied a motion by President Donald Trump's attorney to stay the Summer Zervos defamation case pending appeal, meaning the gathering of evidence known as "discovery" can move forward as both parties await a ruling on the appeal.

Zervos, a former "Apprentice" contestant, filed a lawsuit against Trump in January 2017 in which she alleged that Trump defamed her in 2016 after she said he sexually assaulted her in 2007.

Trump's lawyer, Marc Kasowitz, is appealing the March 20 ruling by New York Supreme Court Justice Jennifer Schecter, who allowed the case to go forward. He wants the appellate court to revisit the matter of whether the Constitution's Supremacy Clause bars a state court from hearing an action against a sitting president -- what would be considered immunity, because it would make the President immune from suit. Schecter ruled it does not. Kasowitz also argues that Schecter erred in denying the President's motion to dismiss or delay the case on First Amendment grounds.

Kasowitz said his motion should be granted on the grounds that New York and federal law both mandate a stay pending appeal, that proceeding with the case could irreparably harm Trump, and that the temporary suspension being sought was not designed to delay the case. But the Appellate Division of the New York Supreme Court denied his motion in a one-page ruling.

"We look forward to proving Ms. Zervos's claim that defendant lied when he maliciously attacked her for reporting his sexually abusive behavior," said Zervos' attorney, Mariann Meier Wang. Kasowitz did not immediately respond to a request for comment on the ruling.

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