The former chair of the Democratic National Committee has said the Democratic party is in "crisis" as members are torn on whether to support Joe Biden’s candidacy for president.
Democrats in Congress have been meeting privately on Capitol Hill to discuss their concerns about Mr Biden’s re-election campaign.
Mr Biden has been defiantly trying to salvage his campaign after a disastrous debate performance against his rival, Donald Trump.
Speaking on RTÉ’s States of Mind podcast, Howard Dean agreed that once this week’s NATO summit in Washington DC is over, there is most likely going to be a push back against Mr Biden’s candidacy.
He said: "First of all, even it weren’t for the NATO meeting, this all takes time. Joe has a long history of being very stubborn, and that’s how get places in politics. He has never given up.
"I’m obviously committed to Biden as long as he's in the race. And then we're just going to have to see what he does. All I want him to do is what's the best for the country."
The next few days will be crucial for Mr Biden as his party discusses, behind closed doors, whether they will continue to back their candidate.
A number of Democrats in the House have already called on the president to end his presidential bid citing worries about his health and ability to be commander-in-chief.
The former governor of Vermont said it is not a question of whether Mr Biden can run the country, rather can he beat Mr Trump in November’s election.
However, he hinted that he is not sure if Mr Biden can do so.
Mr Dean said: "He’s had a very, very strong first time. But this is down to electoral politics.
"I want somebody that can win. I’m not sure about that yet.
"There was a poll this morning that was very damaging for the president which showed that Kamala Harris was more likely to beat Trump than Biden."
