London Underground (LU) plans to axe more than 1,500 jobs and close all but 30 ticket offices, the Rail, Maritime and Transport union has claimed.
It quotes a strategy document, leaked to BBC London, which includes proposals to run driverless trains and replace drivers with "train attendants".
The union said the document "ignores reality in favour of austerity".
LU said the document was a discussion paper and did not represent any agreed proposals.
The confidential document called Operational Strategy Discussion Paper and dated July 2011, looks at how the service will evolve over the next decade and examines "reducing operational costs by up to 20%".
It predicts the closure of most ticket offices by 2016 as more people use contact-less bank cards or Oyster smartcards to pay for their journeys.
Across London 30 ticket offices will remain which will become "travel centres", the paper says.
The strategy document predicts that by 2017 only 20% of trains will be manually operated with drivers in cabs, and beyond 2020 all lines are expected to have "fully remote train operations".
There are also mentions of a recruitment freeze and "imposing" overtime and part-time working.
Bob Crow, the RMT's general secretary, said: "Every single ticket office would be closed, stations left un-staffed and drivers would be thrown out of their cabs without a single thought for passenger safety.
"This ill-conceived and finance-led document ignores reality in favour of austerity and would impact on every single staff member on London Underground.
Transport for London's (TfL) Mike Brown said it was "committed to fully staffed stations" and that it needed to look ahead to see how new technologies could help to continue to provide an efficient and modern underground system.
He added: "This discussion paper was prepared purely to stimulate fresh thinking within London Underground.
"It has not been adopted by LU senior management, the TfL board or the mayor and so does not represent agreed proposals for change."