Sen. Bernie Sanders (I-Vt.) speaks at a news conference last month on Capitol Hill in Washington. (Mandel Ngan/AFP/Getty Images)

Sen. Bernie Sanders (I-Vt.) offered a public apology Wednesday night to female staffers who felt mistreated during his 2016 presidential campaign and said he was unaware at the time of allegations of sexual harassment and pay disparities.

“I certainly apologize to any woman who felt that she was not treated appropriately, and of course if I run, we will do better next time,” Sanders said in a television interview.

The allegations have surfaced in multiple media reports as Sanders mulls a second bid for the Democratic nomination. During an appearance on CNN, he was asked about a New York Times story that detailed episodes of sexual harassment and demeaning treatment that women working for his campaign said were not sufficiently addressed.

Sanders said he was “very proud of the campaign we ran in 2016” but described an operation that “exploded” from just a few paid staffers to more than 1,200 employees in a matter of months.

“I am not going to sit here and tell you that we did everything right in terms of human resources, in terms of addressing the needs that I’m hearing from now, that women felt disrespected, that there was sexual harassment which was not dealt with as effectively as possible,” Sanders told CNN’s Anderson Cooper.

Sanders said safeguards were put in place during his 2018 campaign for reelection to the Senate.

“What I will tell you is that when I ran for reelection in 2018 in Vermont, we put forward the strongest set of principles in terms of mandatory training, in terms of women, if they felt harassed, having an independent firm that they can go to,” Sanders said. “And I think that that’s kind of the gold standard of what we should be doing.”

Asked by Cooper if he was aware of the allegations in 2016, Sanders said his attention was focused elsewhere.

“I was a little bit busy running around the country trying to make the case,” the senator said.

Sanders, who won primaries and caucuses in 22 states in 2016 before ceding the nomination to Hillary Clinton, would join what is shaping up as a crowded 2020 Democratic field if he decided to run again.