LOS ANGELES, Aug. 22 (Xinhua) -- A pro-free trade group in the U.S. agriculture industry Wednesday announced it has purchased billboards and radio ads this week in the state of North Dakota to protest President Donald Trump's tariff policy on behalf of American farmers.

One of the billboards presented by the bipartisan group Farmers for Free Trade rotates with this message: "Secretary Ross, Tariffs Hurt ND Farmers".

The group, co-chaired by former Democratic Senator Max Baucus representing Minnesota and former Republican Senator Richard Lugar of Indiana, showed one of the eight billboards in Fargo, North Dakota's most populous city, which will be visited by Commerce Secretary Wilbur Ross on Thursday.

The billboards have been up since Aug. 20. Radio ads highlighting the impact of tariffs on North Dakota farmers will run on Thursday, when Ross arrives in the state to discuss the impact of tariffs on farmers and the agriculture industry in general.

Brian Kuehl, the group's executive director, said farmers and manufacturers have been patient, giving time to the president to see if his tariffs worked. However, they have received only bad results as prices plummeted and export markets were being taken over by foreign competitors.

"We hope that Secretary Ross hears from North Dakota farmers, manufacturers and workers that it's time to end the trade war, so America's heartland can start thriving once again. It's past time that we open new markets to American exports instead of erecting new barriers," Kuehl said.

Soybean exports to China are the "bottom line" for North Dakotan farmers. Roughly, two-thirds of the state's annual 2-billion-U.S.-dollar soybean crop sale is made in China. However, Chinese buyers have cancelled all orders for food-grade soybean due to the trade war ignited by the White House, the group said.

"If the United States and China don't resolve the trade dispute, farmers may not be able to meet their payments and could lose financing to plant next year's crop. These slashes to the bottom line are unsustainable, and farmers want to see the president focus on open access to international markets for their products." the group said.

The Washington Post reported Wednesday that Trump will make a campaign stop in North Dakota "in the coming weeks."