Los Angeles: Stormy Daniels may face more than $US20 million in damages for violating a "hush agreement" that requires her to remain silent about an affair she alleges she had with President Donald Trump in 2006 and 2007.

The potential damages against Daniels, an actress in adult films whose real name is Stephanie Clifford, were disclosed Friday in a filing in federal court in Los Angeles by Essential Consultants LLC, an entity that was set up by Trump's personal lawyer, Michael Cohen, in 2016 to pay her $US130,000 ($168,000) in exchange for her silence.

The company moved the lawsuit, filed by Daniels last week in California state court against Trump, to federal court, saying that neither Daniels, Trump nor the LLC are California residents and the amount of damages exceeds the $US75,000 limit for a case to proceed in state court. Trump supports the transfer of the case between courts, according to Essential Consultants' filing.

"It could be a strategic move to intimidate them," said Joseph Rothberg, a lawyer with Brutzkus Gubner Rozansky Seror Weber in Woodland Hills, California. "They may be saying, 'We're not going to make it easy for you'."

Federal judges, who are appointed by the president, are perceived as somewhat more conservative than California state court judges, who are elected, according to Rothberg, who isn't involved in the case. On top of that, the anti-Trump sentiment in California may have played a role in the decision, Rothberg said.