Joe Biden has walked back comments he made about the African-American community following his second gaffe in a week as his poll lead over Donald Trump narrows.
The presumptive Democratic presidential nominee issued a three-tweet clarification on Thursday evening after remarks he made in an interview triggered a backlash.
Mr Biden made the comment in passing when asked about normalising relations with Cuba during a conversation with a panel of journalists.
“And by the way, what you all know but most people don't know, unlike the African American community with notable exceptions, the Latino community is an incredibly diverse community with incredibly different attitudes about different things,” he said.
“You go to Florida you find a very different attitude about immigration in certain places than you do when you're in Arizona. So it's a very different, a very diverse community.”
His suggestion that there was a lack of diversity among the African-American community was jumped on by the Trump campaign, which widely shared footage of the remark.
Mr Biden responded with a public statement posted on his official Twitter account which attempted to clean up the message his comments had conveyed.
“Earlier today, I made some comments about diversity in the African American and Latino communities that I want to clarify. In no way did I mean to suggest the African American community is a monolith - not by identity, not on issues, not at all,” he said.
It is the second time this week Mr Biden’s conversations with journalists have led to a backlash. Earlier he had given a heated response when asked if he had taken a cognitive test.
"No, I haven't taken a test. Why the hell would I take a test? Come on, man,” Mr Biden said. The issue has arisen after Mr Trump challenged him to take a test.
He went on: “That's like saying to you, before you got on this program if you had taken a test were you taking cocaine or not. What do you think, huh? Are you a junkie?"
The trip-ups show the political dangers in Mr Biden’s engagement with the media, which is expected to increase markedly after the political conventions later this month.
The former US vice president, now 77, developed a reputation for gaffes during his eight years working under Barack Obama, then the US president.
The Trump campaign had been ruthlessly attacking his verbal trip-ups, with senior figures calling into question his mental acuity via tweets, adverts and interview remarks.
Mr Biden retains a sizable lead over Mr Trump in national polls, but the lead has begun to narrow in the last fortnight.
According to a poll tracker by Real Clear Politics, which takes an average of national polls, Mr Biden was around nine points ahead in late July but is now around 6 points ahead.
The Democratic and Republican conventions are held in back-to-back weeks later this month, with the presidential election held on November 3.