Trump says Biden 'can't stand up to Turkey's Erdogan'
"Let's face it, Joe's shot," Trump said in an interview with the 'Fox and Friends' programme on FOX News.
"You're dealing with people that are very sharp. You're dealing with world-class chess players in the leaders of these countries. I know them all. We do very well with all of them, Erdogan of Turkey," said the US president, who has a friendly relationship with his Turkish counterpart.
"You can't have a guy that doesn't know where he is. You can't have a guy that's afraid to leave his basement because he can't speak any longer," Trump told 'Fox and Friends', a programme widely regarded as his favourite.
Both Trump and his Democratic rival have faced allegations that they are unfit for office.
Trump's comments come after a resurfaced video clip showing Biden fiercely criticising the Turkish president caused uproar in Turkey.
The viral footage of a December interview with The New York Times showed Biden calling for Erdogan's defeat at the ballot box.
"What I think we should be doing is taking a very different approach to him now, making it clear that we support opposition leadership," Biden said, calling the Turkish president an "autocrat" and criticising his intervention in Syria against Kurdish-led forces backed by Washington.
The US should strengthen the Turkish opposition "to be able to take on and defeat Erdogan. Not by a coup but by the electoral process", the Democratic presidential candidate said.
The video clip was widely shared on Turkish social media, with both government officials and opposition figures condemning Biden's statements as impinging upon Turkish democracy.
"We believe that the current US administration would find these undiplomatic remarks unseemly of a presidential candidate of our NATO ally. Turkey is not a country that can be made a tool in domestic political games," Communications Director Fahrettin Altun said on Twitter.
"These remarks are not in line with democracy and the nature of Turkish-American relations," Altun added.
Speaking to 'Fox and Friends' on Monday, the US president said unnamed world leaders had last week asked him to speak with Erdogan as "you're the only one that he'll listen to".
"I don't like saying this publicly, but it happens to be true. I get along with him and he listens," Trump said.
The president has previously described himself as a "big fan" of Erdogan, who so far has managed to avoid US sanctions over Turkey's purchase of Russian S-400 air defence systems.
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