President elect Barack Obama says his administration will begin work immediately to build upon the relationship between the U.S. and Mexico.

Obama met Monday with Mexican President Felipe Calderon. It is a long-standing tradition that the incoming American president meet with his Mexican counterpart before taking office. Obama will be sworn in a week from Tuesday.

Over a lunch of tortilla soup, the two leaders discussed such topics as the North American Free Trade Agreement, border security, immigration and crime.

Obama said the message he brought to the meeting is that his administration will be ready on day one to build a stronger relationship with Mexico. He said existing relations have been strong, but he believes they can be stronger.