Aeromexico will launch flights between Mexico City and London Heathrow from 14 December.
The SkyTeam carrier will operate thrice weekly on the route, using Boeing 767 aircraft.
"The beginning of operations between Mexico and London is a great achievement for all of us who work at this airline, as this destination is very important to the national economy and several key sectors that will also benefit from this new connection," says Andres Conesa, chief executive of Aeromexico Group.
London will be Aeromexico's third European destination, after Madrid and Paris,
The airline will compete on the Mexico City -London against British Airways, which operates four times weekly between the two cities.