Giving evidence to the London Assembly transport committee, Boris Johnson let slip that a cabinet member had been amongst those who called on him to reduce the number of buses on the capital's roads.
But the Mayor said he did not wish to "embarrass" the minister by naming him in public.
The suggestion from the Labour minister came during a conversation about the joys of cycling, Johnson revealed.
But he said he rejected calls from many quarters to cut the number of buses as they were one of the "glories" of the transport system and were envied around the world.
Johnson's recently announced transport plan for London will increase bus fairs by 12.7 per cent and tube fairs by 3.9 per cent. Oyster pay-as-you-go bus journeys will rise from £1 to £1.20.
He also announced that the congestion charge would increase to £10.
