Republican vice-presidential candidate JD Vance blasts Kamala Harris at a campaign rally in St Cloud, Minnesota, on Saturday after she commented on his “loyalty” in a video posted on YouTube.

Earlier, Harris, in a 45-second YouTube video posted on July 16, mentioned: “Vance would be "loyal only to Trump, not to our country and a rubber stamp for [Trump's] extreme agenda.”

Vance defended himself against the allegations made by Harris, calling him only loyal to Trump and not to the country. He highlighted his contributions to the country and mentioned Harris’ failures in tackling the border crises, Fox News reported.

"Now, I saw the other day Kamala Harris questioned my loyalty to this country. That's the word she used; loyalty. And it's an interesting word. Semper Fi: loyalty, because there is no greater sign of disloyalty to this country than what Kamala Harris has done at our southern border," said Vance.

The senator from Ohio discussed the failures that Harris has faced as a vice president.

"And I'd like to ask the vice president, what has she done to question my loyalty to this country? I served in the United States Marine Corps. I went to Iraq for this country. I built a business for this country," he continued.

Vance added: "And my running mate took a bullet for this country. So, my question to Kamala Harris is, what the hell have you done to question our loyalty to the United States of America?"

After the crowd roared with applause, Vance answered his own question.

"And the answer, my friends, is nothing. So, let's send a message to the media. Let's send a message to Kamala Harris. Let's send a message to every hardworking patriot from Minnesota across the country. We are ready to have President Donald J. Trump back, and we're going to work our tails off to make sure it happens," he concluded.

Meanwhile, a Fox News poll shows Republican candidate Donald Trump has 46% support in Minnesota, and the newly-elected Democratic candidate is supported by 52%.