Former President George H.W. Bush has apologized to an actress who accused him of improperly touching her and telling a dirty joke during a photo opportunity four years ago.

"President Bush would never — under any circumstance — intentionally cause anyone distress, and he most sincerely apologizes if his attempt at humor offended Ms. Lind," Bush spokesman Jim McGrath said in a written statement to USA TODAY.

Later in the day, McGrath issued a second statement with a more detailed explanation:

At age 93, President Bush has been confined to a wheelchair for roughly five years, so his arm falls on the lower waist of people with whom he takes pictures. To try to put people at ease, the president routinely tells the same joke — and on occasion, he has patted women’s rears in what he intended to be a good-natured manner. Some have seen it as innocent; others clearly view it as inappropriate. To anyone he has offended, President Bush apologizes most sincerely.

Heather Lind, an actress who stars in the AMC series Turn: Washington's' Spies, described the incident in a since-deleted Instagram post.

“I found it disturbing because I recognize the respect ex-presidents are given for having served. And I feel pride and reverence toward many of the men in the photo. But when I got the chance to meet George H. W. Bush four years ago to promote a historical television show I was working on, he sexually assaulted me while I was posing for a similar photo."

“He didn’t shake my hand. He touched me from behind from his wheelchair with his wife Barbara Bush by his side. He told me a dirty joke. And then, all the while being photographed, touched me again. Barbara rolled her eyes as if to say ‘not again.’ His security guard told me I shouldn’t have stood next to him for the photo.”

The 93-year-old former president, who has a Parkinsons-like disease and other ailments, uses a wheelchair and has difficulty speaking. At a concert his presidential foundation hosted in College Station, Texas, on Saturday to raise money for hurricane relief, he waved briefly at the audience from on stage but didn't make public remarks. He was joined by the other four living former presidents.