Mexico says it opposes a US plan to build more fences along the border in order to control illegal immigration.
President Bush wants tighter security along the Mexican border
Foreign Secretary Luis Ernesto Derbez said his country "does not believe physical barriers are the solution".
President George W Bush announced the construction of more fences in the 3,200km (2,000 miles) border while touring US states earlier this week.
About 10 million Mexicans live in the United States and more than four million are said to stay illegally.
More than a million are arrested every year as they try to enter the US to look for work.
Experts said the migration trend would continue because of the huge wage gap between the US and Mexico.
Mr Derbez insisted his country's position over physical barriers was not only in relation to the United States.
"Mexico voted against the fence Israel built in the Gaza Strip, and against the fences Spain built in Melilla and elsewhere," he said.
The US has already built a border wall between San Diego and Tijuana.
President Bush toured US states to rally support for his strategy to control immigration. He wants tighter security along the Mexican frontier.
He said his government planned to erect wire fences in the urban areas where there was no physical division between the two countries.
Mr Bush added that in the rural areas, barriers preventing the free flow of vehicles from Mexico into the US were to go up.
Many Mexicans try to cross the border with the US in search of a job
He promised the use of unmanned flying drones to help patrol the porous US-Mexican frontier.
"Border security must adapt to the nation's changing needs," Mr Bush said.
He also plans to allow migrants with a job offer to stay in the US temporarily.
Some of his own supporters resist the so-called guest-worker plan. Under his proposal, undocumented aliens would be allowed to get three-year work visas.
They could extend them for an additional three years, under the condition that they would return to their home countries for a year to apply for a new work permit.
But some Republicans say Mr Bush's ideas would reward illegal immigration. Others think the border would still not be secure enough to keep out terrorists and drug-traffickers.