The chair of the Democratic National Committee said Russian hackers continued interfering in the election until 8 November, despite the president’s claim that they stopped in September when he told Vladamir Putin to "cut it out".
Donna Brazile, who is calling for a bipartisan inquiry into the alleged hack, told ABC News that donors and other individuals associated with the campaign were personally harassed and the committee’s computer systems were hacked every day on an "hourly" basis.
"No, they did not stop [in September]," she said.
"They came after us absolutely every day until the end of the election. They tried to hack into our system repeatedly. We put up the very best cyber security – but they constantly [attacked]."
She said the release of Hillary Clinton’s emails was "weaponised", caused confusion and disrupted the daily activities of the campaign.
Ms Brazile also suggested the DNC had insufficient protection from intelligence agencies, despite both the CIA and the FBI concluding that Russians hacked the election to boost Donald Trump.
The FBI was accused of sitting on top of “explosive” information regarding the hack.
"I think the Obama administration ― the FBI, the various other federal agencies ― they informed us, they told us what was happening. We knew as of May," Ms Brazile said. "But in terms of helping us to fight, we were fighting a foreign adversary in the cyberspace. The Democratic National Committee, we were no match. And yet we fought constantly."
Ms Brazile, who as an adviser to Bill Clinton and Al Gore, compared the FBI to the Geek Squad, a tech service at department store Best Buy, which tries to help customers but has limited capabilities.
On Friday the president reasoned that the White House's response to the attacks had been appropriate and that he did not want to risk inciting further hacking which could affect the election.
"I felt that the most effective way to ensure that that didn’t happen was to talk to him directly and tell him to cut it out, and there were going to be serious consequences if he didn’t," Mr Obama said.
"In fact we did not see further tampering of the election process. But the leaks through WikiLeaks had already occurred."
Ms Brazile told ABC News that she was a "little disappointed" with the president's response.
"No, when I saw the president, I was a little disappointed that, you know — we were under constant attack. We never felt comfortable. We didn’t know what was coming next."
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