Trump then noted that China is again buying USA soybeans, through the back door.
Pence is accusing China of using trade, diplomatic overtures and military expansion to spread its influence around the world, including in the Western Hemisphere, and to work against USA interests.
Pence added that Beijing works to steal United States intellectual property, leading to a "new consensus" among U.S. businesses about investing there.
"China always follows the principle of non-interference in others' internal affairs, and we have no interest in meddling in USA internal affairs and elections", Hua said Thursday evening.
Chinese ships routinely patrol around the Senkaku Islands, which are administered by Japan, he said. Canada has moved towards formally engaging China in free-trade talks, though they stalled late a year ago, with little movement since.
Relations between the world's two largest economies have plummeted in recent weeks with Trump placing US$250 billion in tariffs on Chinese goods, in part over charges that Beijing forces U.S. companies to hand over technological know-how.
"China want a different American president", Pence said. "Now China wants to turn these voters against our administration".
At the same time, Pence said Trump continues to forge a "strong personal relationship" with Chinese President Xi Jinping.
"The supplement, created to look like the news articles, cast our trade policies as reckless and harmful to Iowans".
The value of US agricultural trade with Canada and Mexico exploded under the North American Free Trade Agreement, with USA exports jumping from $8.7 billion in 1992 to $38.1 billion in 2016.
After Trump's remark, intelligence and homeland security experts said they didn't know of any Chinese influence operations akin to Russian activities during the 2016 presidential election.
"We're used to tough relations on issues from time to time but not personal attacks", McKenna said.
Pence said China has built an unparalleled surveillance state, and it's growing more expansive and intrusive - often with the help of U.S. technology.
"It built an assurance that Canadian powdered milk would be the cheapest on the world market", he said, adding that this action distorted an otherwise cheap product. He cited the conclusions of career US intelligence officials as he said China is "employing this power in more proactive and coercive ways to interfere in the domestic policies and politics of the United States". Canada also kept at NAFTA dispute-resolution process that the US wanted to jettison. The northern nation exported C$411 billion ($318 billion) of goods to the U.S.in 2017, according to Statistics Canada, compared with C$25 billion to China. It said these include specialized alloys and rare earth metals.
Bloomberg Businessweek cited 17 unidentified intelligence and company sources as saying that Chinese spies had placed computer chips in equipment used by about 30 firms, as well as multiple US government agencies, which would give Beijing secret access to internal networks.
A spokeswoman for China's foreign ministry, Hua Chunying, called Pence's accusations "unwarranted" and a "malicious slander on China".
He urged Google to end development of its "Dragonfly" app that would make it easier to track Internet searches and strengthen Chinese censorship.
He accused Chinese Communist Party officials with "rewarding or coercing American businesses, movie studios, universities, think tanks, scholars, journalists, and local, state, and federal officials".