The London mayor has been branded a "hypocrite" by unions and attacked for "broken promises" over plans to axe Tube ticket office jobs.
Transport union TSSA said Boris Johnson was "elected on the promise to keep all stations open and fully staffed".
Tube bosses announced plans to axe up to 800 jobs last week, under measures to make savings of £16m a year.
Mr Johnson, who heads Transport for London (TfL), said his record on delivering promises was "outstanding".
The TSSA said Mr Johnson plans to cut more than 2,000 hours from booking station opening times across the capital.
The union, which branded the mayor "hypocrite of the year", published a list of all 278 stations which it said would close earlier in the evenings and at the weekends under cuts planned by Mr Johnson.
TSSA leader Gerry Doherty said Mr Johnson "signed our petition in 2007 when Ken [Livingstone] was planning cuts at 40 stations and he was elected on the promise to keep all stations open and fully staffed".
"Now here he is in 2010 planning cuts six times those planned by Ken Livingstone [former London mayor]".
At Mayor's Question Time at City Hall in central London, Labour Assembly member Navin Shah said: "Boris Johnson misled Londoners when he told the assembly that no ticket offices will close under his programme of ticket office cuts."
Green Party Labour Assembly member Jenny Jones said: "Going back on his promise about staffing Tube stations properly isn't only about whether or not we can believe anything the mayor says in the future, but also about his making life less safe and more difficult for thousands of Londoners."
Last week, Tube officials said the post closures would include 100 managers, 450 ticket office posts and up to 200 other jobs.
However a TfL spokesman ruled out compulsory redundancies and said posts would be closed through not filling existing vacancies, voluntary redundancies and redeploying staff.
Mr Johnson said: "Our general record on delivering manifesto promises is outstanding and a tribute to the hard work of everyone who is working flat out to make life better for London."
Mayor of London transport advisor Kulveer Ranger said: "Every station with a ticket office will continue to have one.
"All stations will be staffed at all times when trains are running, and stations will feel safer by moving some staff out of the office and amongst the public."