UPDATE 1-United Airlines closing 3 of 4 international bases for flight crew

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CHICAGO, June 5 (Reuters) - United Airlines Holdings Inc is closing three out of four international bases for flight attendants, according to an internal memo seen by Reuters, saying it is not able to sustain the bases in the current environment.

Airlines are bleeding cash as the coronavirus pandemic has decimated the aviation industry, with international flights hit especially hard by government travel restrictions and a lack of demand.

Chicago-based United is closing its Frankfurt, Hong Kong, and Tokyo bases effective Oct. 1, while keeping London, United’s head of inflight services John Slater said in the Friday memo to crew.

About 840 flight attendants will be affected by the decision, a spokeswoman said, but will be able to transfer to U.S. bases for the October flying schedule, depending on their eligibility to work in the United States.

United has received about $5 billion in government payroll aid under the CARES Act which bans any forced job cuts before October. It has rolled out voluntary early outs for staff including flight attendants in an effort to reduce its headcount and cut costs in the months ahead. (Reporting by Tracy Rucinski Editing by Chris Reese and David Gregorio)