United Airlines said it was cutting an additional 600 flight attendant jobs in response to slumping demand for travel due to a weak global economy.
"The continued challenging economic environment, combined with significantly lower flight attendant attrition, has resulted in United taking the difficult, but necessary step to reduce the number of flight attendants in our operation," parent company UAL said.
"We will again offer our flight attendants a voluntary package, and hope to receive enough responses to prevent any involuntary furloughs."
The cuts represent around four percent of the 13,500 flight attendants at the US carrier.
A company spokesman said voluntary departures would be offered through August 31.
In a related development, the Air Transport Association of America, the industry trade organization for the leading US airlines, reported that passenger revenue fell 26 per cent in May 2009 versus the same month in 2008 - the seventh consecutive month in which passenger revenue has fallen.