Southwest Airlines is looking south of the border-- to expand its U.S.-only service.
Dallas-based Southwest today announced it will sell tickets for travel to Mexico -- beginning in 2010 -- through a deal with Mexican partner Volaris.
Southwest earlier this year reached a similar deal with WestJet Airlines that will allow it to sell travel to Canada late next year.
Southwest offered no details of fares or flight schedules for the deal with Volaris, saying that would be worked out by early 2010.
Volaris was founded in 2006 and serves 23 cities in Mexico.
It operates a new fleet of 18 Airbus A319 and A320 aircraft - unlike Southwest's fleet, which is all Boeing 737s, and much older in average age.
Both the Volaris and WestJet deals are called code-sharing, in which airlines sell tickets on each other's flights and share the revenue.