Trump, Biden trade insults on campaign trail

Trump, Biden take aim at each other during duelling visits to Iowa

Trump, Biden take aim at each other during duelling visits to Iowa

But following a backlash from other presidential candidates and activists, Biden changed his position the next day and said that he now opposes the amendment.

"I guess he's really fascinated by me", Biden said.

"There is no question that what has propelled Vice President Biden to clear front-runner status is his unparalleled experience in contrast to his primary counterparts, but am I hearing gargantuan concerns among Democratic insiders about Biden's advanced age, which is the very byproduct of that experience derived from a lifetime of public service?"

Joe Biden attacked Trump's economic policies in Iowa.

Biden conceded there are questions about his age.

He broadly branded Mr Trump "an existential threat to this country" and said his behaviour is often beneath the office of the presidency.

Speaking in Iowa, a state that is now populated entirely by Democrat presidential candidates, Biden said that Trump was literally an existential threat to America meaning that America would literally cease to exist if Trump continued to be president, which would make it hard for Americans to find a place to park although it would be a lot easier for them to swim to France.

"I'd rather run against Biden than anybody", Trump told reporters on the White House lawn before flying to Iowa. He certainly took that chance to lay out some promises should he win the 2020 United States Presidential polls and one of them is working on a cancer cure.

Mr Biden added that Mr Trump "backed off his threat of tariffs to Mexico basically because he realised he was likely to lose" in manufacturing states such as MI and Ohio. In Council Bluffs, he toured a plant that produces and sells the corn-based fuel additive ethanol, and he signed an executive order he said would help farmers.

The president is expected to highlight his efforts to help farmers hurt financially from Chinese tariffs on USA agriculture products, measures that were imposed previous year after Trump slapped levies on Chinese imports. Though, it read, "Trump pulled America out of the Paris Agreement". Mexico countered that no secret deal was in the works.