(WashingtonPost) - At Cork Wine Bar, owners Khalid Pitts and Diane Gross host corporate dinners, political fundraisers, embassy receptions and an array of other events for clients looking for a casually elegant setting offering more than 200 wines from around the world.

But the couple contend their Logan Circle business would be better off if not for a new player in town who they claim is operating with an unfair and illegal advantage: President Donald Trump, owner of the $212 million Trump International Hotel he opened last fall.

With support from a legal team headlined by the co-founder of Ralph Nader’s advocacy group, Gross and Pitts sued Trump and his D.C. hotel company Wednesday in Superior Court, alleging that the president’s continued ownership of the hotel constitutes unfair competition that damages their business.

“We have events we do here for elected officials, nonprofits, foreign dignitaries, the World Bank, law firms,” Gross said. “Those folks are now being courted to come and want to go there because they see it as advantageous to them to curry favor with the president.”

The White House declined to comment. President Trump has taken steps to insulate himself from the business, resigning from his positions and putting his adult sons, Donald Trump Jr. and Eric Trump, in charge. He pledged to donate profits from foreign clients to the U.S. Treasury.