(Bloomberg) -- President Donald Trump told the United Nations Security Council that China is attempting to interfere in the 2018 midterm congressional elections and alleged Beijing seeks to help his opponents.

His remarks came three days after China placed an advertising supplement in Iowa’s largest newspaper attacking Trump’s trade war with Beijing.

“Regrettably, we’ve found that China has been attempting to interfere in our upcoming 2018 election, coming up in November, against my administration,” Trump told the Security Council on Wednesday at a meeting he hosted. “They do not want me or us to win because I am the first president ever to challenge China on trade and we are winning on trade, we are winning at every level. We don’t want them to meddle or interfere in our upcoming election.”

He did not present evidence for the assertion. While U.S. national security officials are at high alert for an attempt at election interference by a foreign adversary, Russia has been seen as a more likely threat than China.

Dan Coats, the director of national intelligence, told reporters Sept. 12 that China was one of several countries with “capabilities” to interfere in the elections. “It’s more than Russia here that we’re looking at,” he said. But he did not allege that Beijing had taken any action.

China is participating in the meeting as one of five permanent members of the Security Council, and the country’s foreign minister sat nearby as Trump spoke. He didn’t immediately have a chance to respond.

Trump has slapped tariffs on $250 billion in Chinese goods as part of an escalating trade war between the two countries, and he may have been referring both to Chinese counter-tariffs that have targeted politically sensitive industries, especially in Midwest states Trump won, as well as a Chinese public-relations campaign directed at the same areas.

On Sunday the Chinese government bought a four-page advertising supplement in the Des Moines Register, Iowa’s largest newspaper, to highlight the impact of the trade war on the state’s soy farmers. The supplement called the dispute “the fruit of a president’s folly.”

The U.S. intelligence community concluded that Russia interfered in the 2016 election with a covert social media campaign intended to help Trump win. He has grudgingly accepted the conclusion but insists the meddling didn’t assist his campaign.

--With assistance from Alyza Sebenius and Jennifer Jacobs.

To contact the reporters on this story: Jennifer Epstein in Washington at jepstein32@bloomberg.net;Toluse Olorunnipa in Washington at tolorunnipa@bloomberg.net

To contact the editors responsible for this story: Alex Wayne at awayne3@bloomberg.net, Elizabeth Titus

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