Donald Trump has appeared to claim that his presidential rival Joe Biden has dementia in a new tweet.

The claims relate to an incident during a rally on Monday when Biden seemed to forget Utah senator Mitt Romney's name.

After a tweet from a separate account referenced the incident, Trump wrote:

"Mitt can’t be thrilled about this! Joe also said yesterday he’s running for the U.S. Senate (again) and totally forgot where he was (wrong State!).

"Joe has never been a nice or kind guy, so it’s easier to find this obvious & rapidly getting worse 'dementia' unacceptable for USA!"

Per the New York Post, Biden, the Democratic presidential nominee, appeared to lose his train of thought when asked whether it was reasonable to ask questions of Supreme Court Justice nominee Amy Coney Barrett’s catholic faith at her Senate confirmation hearing.

“You may remember, I got in trouble when we were running against that senator who was a Mormon, the governor,” Biden said, apparently in reference to Romney, who ran against President Barack Obama back in 2012.

Biden also appeared to accidentally say that he was running for the Senate at a campaign event in Toledo, Ohio.

“You know, we have to come together. That’s why I’m running. I’m running as a proud Democrat for the Senate, when I ran as a proud Democrat for vice president, and I’m running as a proud Democrat for president. But I promise you this, I will govern as an American president,” the Democratic presidential nominee said per New York Post.

Trump tweeted once again of his rival, writing, ""I’m running as a proud Democrat, for the Senate". Sleepy Joe Biden today. It’s only going to get worse. It is not sustainable for our County - China will own us!!!!"

The news publication reports that Trump also referenced Biden's apparent error at his own campaign rally.

“Sleepy Joe Biden, not a nice guy, by the way … He had a very bad day today,” Trump told the crowd.

“If I ever had a day like he had today, they’d say ‘It’s over. It’s over.’ … He forgot Mitt Romney’s name. He didn’t know what state he was in. And he said today he’s a proud Democrat running for the US Senate”.

Donald Trump has appeared to claim that his presidential rival Joe Biden has dementia in a new tweet.

The claims relate to an incident during a rally on Monday when Biden seemed to forget Utah senator Mitt Romney's name.

After a tweet from a separate account referenced the incident, Trump wrote:

"Mitt can’t be thrilled about this! Joe also said yesterday he’s running for the U.S. Senate (again) and totally forgot where he was (wrong State!).

"Joe has never been a nice or kind guy, so it’s easier to find this obvious & rapidly getting worse 'dementia' unacceptable for USA!"

Per the New York Post, Biden, the Democratic presidential nominee, appeared to lose his train of thought when asked whether it was reasonable to ask questions of Supreme Court Justice nominee Amy Coney Barrett’s catholic faith at her Senate confirmation hearing.

“You may remember, I got in trouble when we were running against that senator who was a Mormon, the governor,” Biden said, apparently in reference to Romney, who ran against President Barack Obama back in 2012.

Biden also appeared to accidentally say that he was running for the Senate at a campaign event in Toledo, Ohio.

“You know, we have to come together. That’s why I’m running. I’m running as a proud Democrat for the Senate, when I ran as a proud Democrat for vice president, and I’m running as a proud Democrat for president. But I promise you this, I will govern as an American president,” the Democratic presidential nominee said per New York Post.

Trump tweeted once again of his rival, writing, ""I’m running as a proud Democrat, for the Senate". Sleepy Joe Biden today. It’s only going to get worse. It is not sustainable for our County - China will own us!!!!"

The news publication reports that Trump also referenced Biden's apparent error at his own campaign rally.

“Sleepy Joe Biden, not a nice guy, by the way … He had a very bad day today,” Trump told the crowd.

“If I ever had a day like he had today, they’d say ‘It’s over. It’s over.’ … He forgot Mitt Romney’s name. He didn’t know what state he was in. And he said today he’s a proud Democrat running for the US Senate”.