'Why do you have to play brinksmanship? Congress is threatening Cat's toehold in Russia," said the dealer, Bill Pigman, referring to Caterpillar Inc., which sold $2 billion of equipment in Russia since 2007.
Russia is one of Caterpillar's top 10 export markets, The New York Times reported Wednesday.
As of Wednesday, Russia will become the 156th member of the WTO and will enjoy lower trade barriers with its members.
The U.S. Congress, however, has yet to recognize Russia as a legitimate trading partner, which allows Russia to create separate trading policies for the United States.
"The Obama administration has not articulated a clear and coherent strategy regarding Russia. Instead, they ask Congress to simply pass permanent normal trade relations and remove Russia from longstanding human rights law," Sen. Orrin Hatch, R-Utah, said in June.
Hatch said the administration, by asking Congress to approve of Russia as a trading partner, was "ignoring Russia's rampant corruption, theft of U.S. intellectual property, poor human rights record, and adversarial foreign policies.''
As a WTO member, however, Russia will drop import tariffs from 15 percent to 7 percent and will include the United States in this change, Russian officials have said.
But Russia can change that policy at any time, putting U.S. companies that export heavily to Russia at risk, the Times said.