Joe Biden has categorically denied allegations from a former Senate aide that he sexually assaulted her in 1993. The presumptive Democratic presidential nominee’s first public comment on the allegation came at a delicate moment for his campaign. “I recognize my responsibility to be a voice, an advocate, and a leader for the change in culture that has begun but is nowhere near finished,” Biden wrote in a Medium post on Friday morning. “So I want to address allegations by a former staffer that I engaged in misconduct 27 years ago. They aren’t true. This never happened.” Biden said he would ask the National Archives to make public any record of a complaint his accuser, Tara Reade, says she filed at the time. Biden said any such document would not be kept at the University of Delaware, among his Senate papers. “I’m saying unequivocally, it never, never happened,” he told MSNBC’s Morning Joe. Reade came forward last month to accuse Biden of sexually assaulting her at a Capitol Hill office complex in spring 1993. His campaign had said the account is false, but Biden had not addressed it. Asked if he remembered Reade, Biden said he did not remember “any type of complaint she may have made”. Morning Joe co-host Mika Brzezinski repeatedly asked if he would authorize a search of his Senate papers. He declined, insisting they “do not contain personnel files”. “They’re not there,” he said. In a statement, however, the National Archives said “any records of Senate personnel complaints from 1993 would have remained under the control of the Senate”. Asked if he was confident no such complaint existed, Biden offered a qualified response: “I know of no one who was aware any complaint was made.” He also said there were no non-disclosure agreements that would prevent women from speaking out. In a statement, Rainn, an anti-sexual violence organization, called for the release of “any and all records that may be relevant, including those housed at the University of Delaware”. “We urge him, his campaign and former staff to cooperate fully and provide complete transparency,” said Heather Drevna, a spokeswoman. The race between Biden and Donald Trump, who himself faces – and denies – accusations of sexual assault and misconduct from more than a dozen women, will be the first of the #MeToo era. Republicans have begun to weaponize Reade’s story while Democrats stand behind Biden. Brzezinski pressed Biden on his support for Dr Christine Blasey Ford, who accused Brett Kavanaugh of sexual assault during his supreme court confirmation hearings. Then, Biden said “it takes enormous courage for a woman to come forward under bright lights, with millions of people watching, and relive something that happened to her”. Ford, he said, “should be given the benefit of the doubt and not be, you know, abused again by the system”. Biden said his position was consistent. Women who come forward deserve “to start off with the presumption that they are telling the truth”, he said. “Then you have to look at the circumstances and the facts and the facts in this case do not exist. They never happened.” Democrats are aware of the importance of female voters. Women are among Trump’s fiercest critics and have organized, voted and run for office in record numbers since his election. Biden has vowed to pick a woman as his running mate. On Friday, Biden pointed to his record as the author of the Violence Against Women Act, and his work as vice-president on combatting sexual assault on college campuses. Yet he has faced renewed scrutiny over his handling of Anita Hill’s testimony during the supreme court nomination of Clarence Thomas, who she accused of sexual harassment, in the 1990s. Before Biden launched his campaign, eight women accused him of touching them or displaying affection in ways that made them uncomfortable. Reade was among them. She did not make her accusation of sexual assault until this year, when she told podcast host Katie Halper Biden allegedly pinned her against a wall and penetrated her with his fingers. Those alleged events were presented to Biden on Morning Joe. He denied them. “I’m not going to go in and question her motive,” Biden said. “I’m not going to attack her. She has a right to say whatever she wants to say but I have a right to say, ‘Look at the facts, check it out.’” In his statement, Biden said women “should be heard, not silenced” but said scrutiny of the “full and growing record of inconsistencies in [Reade’s] story, which has changed repeatedly in both small and big ways” warranted further examination. Tina Tchen, president of advocacy group Time’s Up Now, said: “Today, Vice-President Joe Biden sat down and directly addressed the allegation against him with the seriousness it deserves, something that the current president has never done.” In an interview with conservative radio host Dan Bongino, Trump offered Biden advice: “I would just say to Joe Biden, ‘Just go out and fight it.’ “All of a sudden you become a wealthy guy, you’re a famous guy, then you become president, and people just – people that you’ve never seen, that you’ve never heard of, make charges,” Trump said, before turning back to Biden: “So I guess in a way you could say I’m sticking up for him.” During a White House briefing, the press secretary, Kayleigh McEnany, asserted that the American people have already rendered a verdict on the accusations against Trump, by electing him. But last year the advice columnist E Jean Carroll alleged Trump raped her in the mid-1990s, which the president denied. A defamation lawsuit from another accuser is currently on hold in New York. Biden sought to draw a sharp contrast. “We have lived long enough with a president who doesn’t think he is accountable to anyone, and takes responsibility for nothing,” he said. “That’s not me. I believe being accountable means having the difficult conversations, even when they are uncomfortable. People need to hear the truth.”