United Airlines has seen threats of boycott from around the world following an incident involving American woman Tahera Ahmad, a Muslim chaplain at Chicago’s Northwestern University, who claims she was refused an unopened can of diet Coke.

In a now viral Facebook post, Ms Ahmad stated that she was left in “tears of humiliation from discrimination” after her request was repeatedly refused after the flight attendent said it could be used as a weapon.

She said the incident was rooted in discrimination after the man beside her was given a can of unopened beer by a flight attendant.

“She said, ‘We are unauthorized to give unopened cans to people because they may use it as a WEAPON on the plane.'”

“So I told her that she was clearly discriminating against me because she gave the man next to me an unopened can of beer. She looked at his can, quickly grabbed it and opened it and said, ‘it's so you don't use it as a weapon.’”

Ms Ahmad said she found no support from fellow passengers.

“The man sitting in an aisle across from me yelled out to me, ‘you Moslem, you need to shut the F** up’,” she said.

“I said, ‘what?!’ He then leaned over from his seat, looked me straight in the eyes and said, ‘yes you know you would use it as a WEAPON so shut the f**k up.’ I felt the hate in his voice and his raging eyes.

“I can't help but cry on this plane because I thought people would defend me and say something. Some people just shook their heads in dismay.‪”

Social media has since rallied around Ms Ahmad, sending the hashtags #BoycottUnitedAirlines and #UnitedforTahera trending.

Twitter users described the incident as foul and absurd, with many calling for United to take responsibility for the incident.

Disgusting to hear a woman not being allowed an unopened can while on a flight because she's a Muslim. #unitedfortahera #IslamophobiaISREAL — Bonjour. (@HassnainSafdar) May 31, 2015

I refuse to fly @united until they learn how to not discriminate. Pathetic behavior. #unitedfortahera pic.twitter.com/BZJJDZ6Mnq — Omar Suleiman (@omarsuleiman504) May 30, 2015

What turns a closed can of coke into a WMD? Only Muslims, say @united airlines. I *fully* support #BoycottUnitedAirlines #unitedfortahera — Abu Eesa Niamatullah (@Niamatullah) May 30, 2015

The airline has also faced backlash on its Facebook page, prompting one user to create a separate page for complaints.

United has issued a statement on the incident, describing it as a “misunderstanding regarding a can of diet soda.”

“The inflight crew met with Ms Ahmad after the flight arrived in Washington to provide assistance and further discuss the matter,” it read.

“Additionally, we spoke with Ms Ahmad this afternoon to get a better understanding of what occurred and to apologize for not delivering the service our customers expect when traveling with us.”

Ms Ahmad said the response was disappointing.

“United has dismissed my entire narrative and trivialized it to a can of soda,” she said.

“It is truly disheartening when the discrimination of Americans as myself who are working hard every day to promote dialogue and understanding is disregarded and trivialized.”

She said she did not want the flight attendant involved to be fired, rather for the airline to take “corrective measures within their training to prevent this from happening again regardless of their race, religion, gender, sex, or socioeconomic background.”