US President Donald Trump has slammed his predecessor Barack Obama over his criticism of how the incumbent administration has handled the coronavirus pandemic in the country which currently accounts for the highest number of COVID-19 cases and deaths in the world.

"Look, he was an incompetent president," Trump said of Obama, after returning to the White House by Marine One on Sunday. "That's all I can say. Grossly incompetent."

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One of the most corrupt and incompetent in US history'

Later in a tweet, Trump called the former Obama administration "one of the most corrupt and incompetent in US history", reports Xinhua news agency.

Trump also claimed that Obama and his Vice President, Joe Biden, were the reasons why he's in the White House. The comments came a day after Obama issued a thinly veiled criticism of the Trump administration's handling of the coronavirus pandemic.

"More than anything, this pandemic has fully, finally torn back the curtain on the idea that so many of the folks in charge know what they're doing," Obama said during a virtual commencement speech on Saturday. "A lot of them aren't even pretending to be in charge."

In a private call with supporters earlier this month, details of which was leaked to media outlets, Obama called the Trump administration's coronavirus response "an absolute chaotic disaster".

"It's part of the reason why the response to this global crisis has been so anaemic and spotty," Obama reportedly said. "It would have been bad even with the best of governments."

 US  accounts for world's highest number of Covid-19 

coronavirus mutation
Representational ImagePixabay

The US currently accounts for the world's highest number of cases and deaths at 1,486,515 and 89,562, respectively, according to the Johns Hopkins University.

The Trump administration has aggressively defended its handling of the public health crisis, while critics have pointed out that its leaders and officials ignored early warnings, were slow to act and not responding adequately, and tried to politicize the situation to shift blames.

The trading of barbs also occurred against the backdrop that Trump, the presumptive Republican presidential nominee, was set to be challenged by Biden, the presumptive Democratic nominee, in this year's election. Obama has endorsed Biden for the White House.