The £25m scheme, which would be privately-funded, would connect the Greenwich Peninsula on the south side with the Royal Docks on the north bank.
Cars departing at 30-second intervals would take five minutes to ferry passengers between the O2 and ExCeL Olympic venues, and travel at a height of about 50m.
London Mayor Boris Johnson revealed that a period of public consultation will take place until 2 August, with a planning application due next year.
Johnson said: “A cable car spanning the majestic Thames would not only provide a unique and pioneering addition to London’s skyline, but also offer a serene and joyful journey across the river.
Discussions are ongoing with a number of private sector organisations that have expressed interest in the project.
A scheme was first mooted by AEG, owners of the Millennium Dome, in 2006. At the time the firm said it had held initial talks with Doppelmayr, which has built similar systems for ski slopes and shopping malls.
Cities already operating cable car systems include Barcelona, Cologne, Hong Kong, Lisbon, New York and Singapore.