New York restaurateurs Danny Meyer, Tom Colicchio, and James Mallios of Amali endorsed a restaurant workers organization today as it filed a lawsuit against President Donald Trump — alleging that Trump’s ownership of hotels and restaurants puts other restaurants at a disadvantage.

On Tuesday, the Restaurant Opportunities Centers United, or ROC, joined a suit filed by government watchdog group Center for Responsible Ethics in Washington that claims Trump’s refusal to give up ownership of his businesses violates an “emoluments” clause of the Constitution, according to the Daily News. The clause bans presidents from accepting cash from foreign governments.

The lawsuit alleges that foreign dignitaries will “curry favor with the administration,” ROC said in a statement announcing why they decided to join the lawsuit.

“As a hotel and restaurant owner, the President puts restaurateurs and restaurant workers nationwide at a grave disadvantage, pushing foreign dignitaries to patronize his establishments rather than go to others,” the statement says.

Trump’s home base of New York owns several buildings in the city that bear his name, including a hotel near Columbus Circle and the famous residential Trump Tower in Midtown. The Trump International Hotel houses celebrity chef Jean-Georges Vongerichten’s flagship three Michelin-starred fine dining restaurant Jean-Georges, while the Trump Tower is the location of the much-maligned Trump Grill. Last fall, Trump took Mitt Romney and Republican National Committee Chairman Reince Prebus to Jean-Georges.

Mallios and Colicchio are members of ROC United and say they predict their restaurants will lose business because of Trump’s involvement in local restaurants. Amali, a Mediterranean restaurant on the Upper East Side near Midtown East, often hosts foreign dignitaries, Mallios says in a statement.

“There is no question in my mind that foreign companies, countries, and individuals will feel compelled or advantaged by choosing Trump establishments over our own,” the restaurateur says. “While I always expected to compete against the best restaurants in the toughest restaurant market in the world, I never thought I would have to compete against the pecuniary interests of the President of the United States.”

ROC represents more than 200 restaurants and nearly 25,000 restaurant workers nationwide. Meyer voiced support for ROC’s mission in a statement, and chef and restaurateurs Alice Waters and Paul Saginaw of Zingerman’s in Ann Arbor endorsed the lawsuit.

Trump has previously said that his business will go into a trust run by his sons, Eric and Donald Jr., but reports later found that he is still the ultimate financial benefactor — a move that ethics experts found less than satisfying.