Mesa wants out
Presidency Minister Jose Galindo delivered the resignation, which was broadcast on television.
Congress will most likely meet today and analysts said it could reject the surprise move announced by Mr Mesa on Sunday after 17 months in office.
If Congress accepts the resignation, it will be the second time a Bolivian president has quit in less than two years amid protests by the indigenous majority centring mostly on the issue of how to develop the country’s massive gas reserves.