During a virtual town hall on Saturday, the Democratic presidential candidate said
The New York Times report, if true, represents a “shocking revelation”.
“Not only has he failed to sanction or impose any kind of consequences on Russia for this egregious violation of international law, Donald Trump has continued his embarrassing campaign of deference and debasing himself before Vladimir Putin,” Biden said, referring to the Russian president.
Biden pledged retaliation if he becomes president.
“If I’m elected president, make no mistake about it, Vladimir Putin will be confronted and we’ll impose serious costs on Russia,” Biden said.
The comments came on Saturday after the White House denied President Donald Trump had been briefed on intelligence that reportedly showed Russia had offered bounties to militants if they killed US soldiers in Afghanistan.
The rewards purportedly gave incentives to the guerrillas to target US forces, amid Trump's attempts to withdraw troops - meeting one of the militants' key demands - and end America's longest war.
It was first reported by
The New York Times on Friday. The newspaper, citing anonymous officials, said that Trump was briefed on the findings in March, but has not decided how to respond.
Press secretary Kayleigh McEnany said "neither the President nor the Vice President were briefed on the alleged Russian bounty intelligence."
But she added: "This does not speak to the merit of the alleged intelligence but to the inaccuracy of the story erroneously suggesting that President Trump was briefed on this matter."
That left open the possibility such intelligence does exist.
The Taliban have denied the report, reiterating that it was committed to an accord signed with Washington in February that paves the way for withdrawing all foreign forces from Afghanistan by next year.
The militants also said homemade explosives account for most fatalities among US forces.
"The nineteen-year jihad of the Islamic Emirate is not indebted to the beneficence of any intelligence organ or foreign country," the Taliban said in a statement issued in Kabul.
The group, widely believed to have received years of support from Pakistani intelligence, also denied previous US accusations it was given arms by Russia.
"The Islamic Emirate has made use of weapons, facilities and tools ... that were already present in Afghanistan or are war spoils frequently seized from the opposition in battles," it said.
Russia has also denounced the report, with its embassy in Washington tweeting that the "baseless and anonymous accusations" in the
Times story had "already led to direct threats to the life of employees" at its embassies in Washington and London.
"Stop producing #fakenews that provoke life threats, @nytimes," it added in a later tweet.
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