But Mr Derbez said Mexico had proved it was successfully fighting violence and drug-trafficking in the region.
BBC: NEWS | Americas | Mexico raps US warning on safety
2.
Mr Garza, the US ambassador in Mexico City, also raised the issue in a letter to Mr Derbez and the country's attorney-general.
BBC: NEWS | Americas | Mexico raps US warning on safety
3.
Eduardo Sojo, a long-time economic adviser to Mr Fox will become the president's chief of staff, while Luis Ernesto Derbez, another aide, will be economy minister, a new post handling trade, industry and small business.