Hillary Clinton might be on one side of the border, then the other when it comes to issuing driver's licenses to illegal immigrants, but Mexican officials know exactly where they stand: no licenses for illegals.

All of Mexico's 31 states require foreign residents to hold a valid visa if they want a Mexican license, according to a survey published Thursday in The Arizona Republic.

Click here to read the complete story in The Arizona Republic.

"When it comes to foreigners, we're a little more strict here," Alejandro Ruíz, director of education at the Mexican Automobile Association, told the newspaper.

Immigrant drivers became an overnight national campaign issue when Democratic presidential hopeful Hillary Clinton responded to a debate question by declared her support for a move by New York Gov. Eliot Spitzer to issue licenses to illegal immigrants.

"It makes a lot of sense," Clinton said during the Oct. 30 debate.

She backed away from that support Wednesday when Spitzer announced he was backing off the plan.

Eight U.S. states allow drivers to get licenses without proving they are legal residents, the newspaper reported.

Mexicans account for more than half of the 12 million undocumented residents, according to the Pew Hispanic Center.

Because of the number of illegal Mexicans residing in the U.S., America's southern neighbor has battled to open the licensing process in all 50 states.

But licensing offices in all of Mexico's 31 states -- and Mexico City -- told The Arizona Republic that proof of citizenship is required.

Temporary tourists can drive using their foreign licenses, the newspaper reported, the same temporary exemption granted visitors to the U.S.