I am an Indian citizen with a green card. I may be going to Mexico for 4-5 days for work related meetings. Do I need a visa, or just show up in MX with my passport and GC?
Entering to Mexico is between your country (India) and Mexico. You need green card for your return back to U.S.
You still have to show your passport. You just have an option not to show your GC. Those who are from countries that do not have visa waiver agreement with Mexico must show both passport and the GC. if you travel by land, however, your GC alone should be enough.As a EU citizen I have visa waiver program for Mexico. So it means I have basically 2 options when entering Mexico or Canada:
1) Showing my green card
2) Showing just my passport
Is that correct?