As the race for the 2020 presidential election gathers pace, the bitter war of words between US President Donald Trump and his main political rival Joe Biden is expected to escalate.
Seen as the frontrunner for the Democratic nomination, Mr Biden has been the main target of Mr Trump's verbal broadsides so far.
But some insults, it seems, go too far, even for President Trump.
On Sunday Mr Trump tweeted a rare, albeit backhanded, defence of Mr Biden in response to a vicious verbal attack by North Korea.
The surprising tweet was addressed to "Mr Chairman", an apparent reference to North Korea's leader Kim Jong-un.
In the tweet, Mr Trump said although Mr Biden was "sleepy and very slow", he was "not a rabid dog", as North Korea had called him.
Mr. Chairman, Joe Biden may be Sleepy and Very Slow, but he is not a “rabid dog.” He is actually somewhat better than that, but I am the only one who can get you where you have to be. You should act quickly, get the deal done. See you soon! https://t.co/kO2k14lTf7
— Donald J. Trump (@realDonaldTrump) November 17, 2019
End of Twitter post by @realDonaldTrump
The president's comments were included in a retweet of a conservative commentator's post about North Korea's attack on Mr Biden.
North Korea had lambasted Mr Biden for having the "temerity to dare slander the dignity" of its leader, Mr Kim.
"Rabid dogs like Biden can hurt lots of people if they are allowed to run about," a statement, carried North Korea's official KCNA news agency, said on Thursday. "They must be beaten to death with a stick."
It is not clear what drew the ire of North Korea, though Mr Biden has been critical of the Trump-Kim summits this year and last.
In response to the North Korean jibe, Mr Biden said he saw such insults "as a badge of honour".
In contrast, Mr Trump's relationshRead More – Source