DES MOINES, Iowa (AP) — The Latest on Donald Trump and Joe Biden visiting Iowa (all times local):

1 p.m.

Preparing to hold dueling events in Iowa Tuesday, President Donald Trump is employing schoolyard taunts for his leading Democratic presidential rival, former Vice President Joe Biden.

Trump says of Biden, "I think he's the weakest mentally" of the 2020 field and referred to Biden as "a dummy." Trump addressed reporters from the White House before departing for Iowa to deliver remarks on energy and attend a political fundraiser.

Trump says Biden was wrong to say that China was not a competitor of the U.S., and says that during the Obama administration, China "ate our country alive."

Biden is holding events in the first-in-the-nation caucus state Tuesday, including delivering a speech in which he is expected to call Trump an "existential threat" to the nation.

___

8:20 a.m.

The White House says Joe Biden's plan to call President Donald Trump an "existential threat" to the nation is "truly laughable" as the two politicians converge in Iowa on Tuesday.

White House press secretary Sarah Sanders says she's not sure whether Trump will respond to the former vice president, whose prepared remarks criticizing Trump were released ahead of his Iowa speech.

Sanders says, "The idea that he would say that the president poses any type of threat is truly laughable considering he was part of the administration that allowed Russia to interfere in our election."

Sanders says Biden was a key member of an Obama administration that also allowed China to grow and North Korea to test missiles. She says Biden has "got a lot of explaining to do."

Biden plans to use his Iowa visit to criticize Trump's economic policy.

___

5:40 a.m.

Democratic presidential candidate Joe Biden plans to use his visit to Iowa to criticize President Donald Trump's economic policy as hurting those very voters who helped elect him.

Biden says in remarks prepared for delivery on Tuesday that Trump "thinks he's being tough" and "it's easy to be tough when someone else is feeling the pain." Biden plans to speak in blue collar Ottumwa, the seat of Wapello County.

Trump was the first Republican to carry the economically struggling county in southeast Iowa since Dwight Eisenhower.

Biden asks in his prepared remarks, "How many sleepless nights do you think Trump has had over what he's doing to America's farmers? Zero."

Trump has attacked Biden regularly and on a recent state visit to Japan echoed North Korean leader Kim Jong Un's description of Biden as "low IQ."

___

12:20 a.m.

After months of jabbing from afar, President Donald Trump and Democrat Joe Biden are overlapping Tuesday in Iowa, a state that's critical to their political futures.

The former vice president is in Iowa hoping to hold his party's front-runner role. Trump seeks to shore up support in a key Midwestern state he wrested from Democrats in 2016.

The day could offer a glimpse of a Trump-Biden matchup in this battleground state.

Trump begins his trip in Council Bluffs to speak at Southwest Iowa Renewable Energy, which produces and sells the corn-based fuel additive ethanol. He will later address an Iowa GOP dinner in Des Moines.

Biden is coming two days after nearly 20 Democratic rivals were in Iowa for a state party dinner. Several took veiled shots at his absence.