WASHINGTON, May 31 (Xinhua) -- Following U.S. President Donald Trump's announcement Thursday that his administration would impose tariffs of 5 percent on all Mexican imports, business groups, officials and experts have responded by denouncing the decision, urging the president to give it a second thought.

"We appeal to President Trump to reconsider plans to open a new trade dispute with Mexico," said David Herring, president of the National Pork Producers Council (NPPC), in a statement Friday.

"American pork producers cannot afford retaliatory tariffs from its largest export market, tariffs which Mexico will surely implement," added Herring, who is also a pork producer from Lillington, North Carolina.

Trump announced in a tweet Thursday that the 5 percent tariffs covering the full spectrum of Mexican products sold to the United States will be implemented on June 10, and will remain in effect until Mexico has stopped the flow of "illegal migrants" into the United States via Mexico.

The White House said in a statement issued following the president's tweet that the planned duties will be increased to 25 percent on Oct. 1 and permanently remain at that level "unless and until Mexico substantially stops the illegal inflow of aliens coming through its territory."

Citing Iowa State University economist Dermot Hayes' estimates, the NPPC said that for most of the last year, U.S. pork producers have lost 12 U.S. dollars per hog in trade with Mexico, as the latter imposed counter-tariffs in retaliation to the U.S. tariffs including on steel and aluminum products.

Washington exempted Mexico from the metal tariffs on May 17, and Mexico lifted the retaliatory tariffs.

"Dr. Hayes projects that the U.S. pork producers will lose the entire Mexican market, one that represented 20 percent of total U.S. pork exports last year, if they face protracted retaliation," the NPPC statement said.

It added that as of April 2019, U.S. pork exports to Mexico declined 28 percent from the same period last year.

At a time when the Trump administration is pushing for congressional approval of the United States-Mexico-Canada Agreement (USMCA), such a tariff threat is believed to hamper the ratification of the new trade deal as it needs to pass in the three nations' respective legislatures.

The NPPC urged the Trump administration to "move forward with ratification" of USMCA and preserve "zero-tariff pork trade in North America for the long term."

U.S. Senate Finance Committee Chairman Chuck Grassley in a statement criticized Trump's tariff move against Mexico, saying it is "a misuse of presidential tariff authority and counter to congressional intent."

"Trade policy and border security are separate issues," said Grassley, an Iowa Republican. "Following through on this threat would seriously jeopardize passage of USMCA," he warned.

The newly announced tariffs are also expected to particularly harm the U.S. automobile sector, one of the major concerns in USMCA. The American Automotive Policy Council (AAPC), a Washington-based group representing U.S. automakers such as Chrysler, Ford and General Motors, said the USMCA "relies on duty free access to be successful."

The imposition of tariffs against Mexico, the AAPC said, will undermine the USMCA's "positive impact and would impose significant cost on the U.S. auto industry."

Automobiles worth a total of 52.6 billion dollars were shipped to the United States from Mexico in 2018, and another 32.5 billion dollars in auto parts entered the U.S. market from Mexico during the same period, according to data from the U.S. Department of Commerce.

In an opinion piece carried by the Forbes magazine's website on Friday, author Phil Levy argued Trump's latest tariffs against Mexico violated the recently-negotiated USMCA, and showed that "President Trump is unwilling to honor trade agreements and will repeatedly turn to tariffs to resolve an unending list of grievances."

Levy said that there is "astonishingly little policy coordination within the administration, leading to incoherent actions." He added that the tariff threat against Mexico "demonstrates that the (USMCA) deal does nothing to limit protection between the countries and kills the possibility of cooperation with Mexico."