NEW YORK, July 31 (UPI) — A letter allegedly sent by Delta Airlines gives an apology to a disabled man for forcing him to crawl up a boarding ramp when a wheelchair was lacking, he said.

Baraka Kanaan of Maui, Hawaii, a former college professor and current director of a non-profit organization, said he received the letter after he filed a lawsuit in federal court July 23.

The suit says in part Kanaan “crawled hand over hand through the main cabin and down a narrow flight of stairs and across the tarmac to his wheelchair” at a Massachusetts airport in July, despite previous assurances his wheelchair accommodations would be met.

“They gave me an ultimatum. You can find a way off this plane on your own or you can go back to Maui where you live,” Kanaan told the New York Daily News Tuesday.

The letter, from Delta Agent Megan Buchanan, apologized “for any distress or discomfort caused when it was necessary to board/disembark in Nantucket by crawling up and down the plane’s stairs.”

The newspaper said it had seen the letter, but its authenticity was not confirmed by Delta, which the report said had previously refused comment because of pending litigation.