Former Vice President Joe Biden on Sunday addressed an allegation that he inappropriately kissed a Nevada candidate for statewide office in 2014, saying in a statement that "not once — never — did I believe I acted inappropriately."

“In my many years on the campaign trail and in public life, I have offered countless handshakes, hugs, expressions of affection, support and comfort," Biden said. "And not once — never — did I believe I acted inappropriately. If it is suggested I did so, I will listen respectfully. But it was never my intention. I may not recall these moments the same way, and I may be surprised at what I hear."

"But we have arrived at an important time when women feel they can and should relate their experiences, and men should pay attention," he said. "And I will. I will also remain the strongest advocate I can be for the rights of women. I will fight to build on the work I’ve done in my career to end violence against women and ensure women are treated with the equality they deserve. I will continue to surround myself with trusted women advisers who challenge me to see different perspectives than my own. And I will continue to speak out on these vitally-important issues where there is much more progress to be made and crucial fights that must be waged and won."

Joe Biden at the First State Democratic Dinner in Dover, Delaware, on March 16. Jonathan Ernst / Reuters

In a New York magazine piece published Friday, Lucy Flores, the 2014 Democratic nominee for Nevada lieutenant governor, said that before a campaign event where Biden was set to campaign for her and other Democratic candidates, the then-vice president approached her from behind, placed his hands on her shoulders, smelled her hair, and gave her an uncomfortable kiss on the back of the head.

"I felt him get closer to me from behind," Flores wrote. "He leaned further in and inhaled my hair. I was mortified. I thought to myself, 'I didn’t wash my hair today and the vice-president of the United States is smelling it. And also, what in the actual f---? Why is the vice-president of the United States smelling my hair?' He proceeded to plant a big slow kiss on the back of my head. My brain couldn’t process what was happening. I was embarrassed. I was shocked. I was confused."

NBC News has not independently verified that the incident Flores alleges took place, but has reviewed correspondence in which she referred to an incident involving the former vice president years before.

Flores showed The Daily Beast correspondence that the news site reported "gives credence to Flores’ claim to the extent that it shows it was an incident she talked about before going public this Friday."

“I don't believe that it was a bad intention," Flores said Sunday on MSNBC's Kasie DC. "I’m not in any way suggesting that I felt sexually assaulted or sexually harassed. I felt invaded. I felt there was a violation of my personal space.”

The allegation comes as Biden weighs whether to enter the 2020 presidential race. Already, 2020 Democratic presidential candidates Julian Castro, the former Housing and Urban Development secretary, and Elizabeth Warren, a Massachusetts senator, have said they believe Flores.

Vermont independent Sen. Bernie Sanders, who also is running for the Democratic presidential nomination and whom Flores endorsed during his 2016 presidential bid, said Sunday on CBS’s "Face the Nation" that he had "no reason not to believe" Flores' allegation.

"And I think what this speaks to is the need to fundamentally change the culture of this country and to create environments where women feel comfortable and feel safe," Sanders said. "And that’s something, we’ve got to do.”

When asked about the allegation on NBC's "Meet the Press," Senate Minority Whip Dick Durbin, D-Ill., said, "Certainly one allegation is not disqualifying, but it should be taken seriously."

Coming to Biden's defense was Henry Munoz, the co-founder of Latino Victory Project and an organizer of the 2014 campaign rally in question. Munoz said that he has "thoroughly reviewed photographic documentation from the event, and spoken to nearly every principle in attendance, as well as staff associated with the event. To the best of our recollection, at no time were Lucy Flores and Vice President Biden alone."

Munoz said Flores is "a good friend" and Biden is so close to him that he "presided over my own marriage. Munoz said he firmly believes that "women need to be supported and heard and that there is a reckoning in our culture that is long overdue."

"These are both individuals that I love and respect, and who have been supported by and who have supported the organization I co-founded to lift Latinx candidates," he said. "Yet at no time were these two leaders alone together and I, and the organization I cofounded and those in attendance, do not believe that circumstances support allegations that such an event took place.”

A former Biden aide, Cynthia Hogan, also defended the former vice president in a statement Sunday, saying he treated women staff members "with respect and insisted that others do the same," and promoted several women, including herself, to leadership roles.

Flores said Sunday on CNN's "State of the Union" that she was "shocked" by Biden's alleged behavior and said she believes it is "disqualifying" to his possible presidential bid.

Flores, who said she is a supporter of Sen. Bernie Sanders, I-Vt., told CNN, "Never do I claim that" the incident she described "rises to the level of sexual assault."

Rather, she said, it was “completely inappropriate” and shouldn't happen in any setting.

A spokesperson for Biden said in a statement Friday that such allegations should be taken seriously but that Biden does not remember the incident.

"Neither then, nor in the years since, did he or the staff with him at the time have an inkling that Ms. Flores had been at any time uncomfortable, nor do they recall what she describes," the spokesperson said. "But Vice President Biden believes that Ms. Flores has every right to share her own recollection and reflections, and that it is a change for better in our society that she has the opportunity to do so. He respects Ms. Flores as a strong and independent voice in our politics and wishes her only the best."