The economy could continue to expand for another one to three years, but the Trump administration's trade policy could prove to be one of the "flies in the ointment" that ends the recovery, according to J.P. Morgan Chase CEO Jamie Dimon.

Dimon, chairman of the Business Roundtable, made the comments on a conference call with reporters about the CEO group's latest quarterly survey, which showed a high level of concern among chief executives about the potential negative effects of Trump's trade actions. The Roundtable's Economic Outlook Index fell slightly from record highs, in its first decline in CEO sentiment in two years.

"Trade is a very complex thing with many layers. When you talk about it, slogans are very different than policies that makes sense," said Dimon. He said everyone wants free and fair trade but he objected to U.S. Trade Representative Robert Lighthizer's comments, when he suggested the policies of pro-business lobbies have created the current trade deficit and have hurt everyday Americans.

Dimon said the U.S. economy is strong and broad-based, and the recovery could continue for another one to three years. However, "one of the flies in the ointments is this trade stuff. This trade stuff is not only directly affecting decision but it also increases uncertainty and uncertainty is not a friend of the economy."

Joshua Bolten, the Business Roundtable's president and CEO, told the conference call the Roundtable has had a positive relationship with the White House but the administration is not listening to its concerns on trade, including the tariffs placed on steel and aluminum on national security grounds.

"The threat of doing the same thing with autos is also of deep concern to our members," said Bolten. So is "the threat of a withdrawal from NAFTA, which has worked extremely well, not just for the Canadian and Mexican but U.S. economy and American workers, and we're going to keep advocating for constructive pro-growth trade policies that do not undermine our competitiveness."

In the Business Roundtable survey, CEOs were slightly less optimistic about capital spending, hiring and sales growth, but Bolten said it's not clear how much of the capital spending plans, still near record highs, was impacted by trade concerns.

"What I can tell you is anecdotally is that the administration's trade policy is a huge concern to almost every member of our organization to the extent they see clouds on the economic horizon. The risk of trade wars and the administration's policies that are contributing to that are very high on the list of things our members are concerned about," Bolten said. He added that there are important issues that the administration is trying to correct including concerns about Chinese trade practices on such things as intellectual property.

He and Dimon also said some of the issues the U.S. is negotiating for in revisions to the North American Free Trade Agreement are unnecessary. "There are some things we are negotiating for in NAFTA that we just think are mistakes," said Dimon.

Dimon said businesses prefer the arbitration rules currently in NAFTA and do not want to be subject to courts when there are trade issues, a position pushed by the Trump administration.

Dimon also said the U.S. does not need a "sunset" provision in NAFTA, as the U.S. already has the ability to withdraw. That provision has been strongly objected to by Canadian Prime Minister Justin Trudeau who says it creates business uncertainty.

Separately, Lighthizer released a statement saying the NAFTA negotiations continue, but that the three countries are not close to a deal. "There are differences on intellectual property, data localization, agricultural market access, de minimis levels, energy, labor, rules of origin, geographical indications, and much more. We however are making progress and will continue to engage in negotiations. I look forward to working with my counterparts to secure the best possible deal for American farmers, ranchers, workers, and businesses at the earliest time," Lighthizer said.

According to the latest quarterly Business Roundtable CEO Economic Outlook Survey, the CEO Economic Outlook Index slipped to 111.1 in the second quarter, down from a record 118.6 in the first quarter, the first decline since before President Donald Trump was elected president.

That represents CEO optimism about hiring, capital investment and sales growth, and it fell in the second quarter for the first time in two years amid concerns that trade conflicts could drive up costs for consumers and business.

Fifty-eight percent see a moderate risk of lower U.S. economic growth as a result of Trump's trade approach, while 41 percent see a serious risk of lower growth. The majority expect input costs for businesses to rise, with 47 percent seeing a serious risk of higher costs and 43 percent seeing a moderate risk.

The White House did not respond to a request for comment on the decline in CEO confidence.

— CNBC's Kayla Tausche contributed to this story.