Kew Gardens station's ticket office could close as London Underground begins its consultation over ticket office closures.
The station is served by District line trains, as well as London Overground services.
Labour London Assembly member Murad Qureshi said the move is set to "mask significant cuts in staff numbers".
He added: "The argument isn’t so much about whether staff are based behind a counter of not, it’s about whether there are actually enough staff left to provide assistance to passengers, particularly given that elderly and disabled passengers often rely on them to help them use the station.
"I'll be looking carefully at these proposals to ensure stealth cuts to staffing numbers are buried in the detail.
"After years of fare rises passengers will feel well and truly ripped off if it looks like they are getting a reduced service yet paying inflated fares."
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