MEXICO CITY - President Barack Obama, outlining plans to help Mexico combat drug violence, promised Thursday to resurrect a treaty against arms trafficking that has been stuck in Congress for 12 years but rebuffed Mexico's demands to curb sales of assault weapons in the United States. Speaking during his first official trip to Mexico, Obama said he will try to persuade lawmakers to finally approve the treaty known as CIFTA, which was signed by President Bill Clinton in 1997 but has never been ratified by the U.S. Senate.
However, Obama showed little appetite for reviving the 1994-2004 Assault Weapons Ban. During a joint press conference in Mexico City, Mexican President Felipe Calderón blamed the end of the ban for the increasing firepower wielded by drug cartels.
Calderón's 2-year-old crackdown against the cartels has ignited a firestorm of violence that has killed more than 10,000 people since late 2006. On Wednesday, a shootout between troops and a convoy of traffickers in southwestern Mexico killed 15 drug-gang members and one soldier hours before Obama arrived in the country.
Obama, who acknowledged the United States shares a responsibility for the bloodshed in Mexico, said that he still believes the Assault Weapons Ban "made sense" but that he wants to concentrate on measures against gun smuggling, not gun sales. Many members of Congress, including Democrats, have vowed to fiercely oppose any revival of the ban.
The ban prohibited sales of semiautomatic weapons with certain combinations of military-style features, such as folding stocks, large magazines and flash suppressors.
Opponents of the ban say that the weapons actually fire smaller bullets than some other rifles and that it is unconstitutional to ban a gun simply because of how it looks.
"None of us is under the illusion that reinstating that ban would be easy, and so what we've focused on is how we can improve our enforcement of existing laws," Obama said.
Obama tried to cast his visit to Mexico as the start of a new era of cooperation between the countries. But the disagreement over weapons sales was only one of several divisions that emerged during a news conference following his meeting with Calderón.
At one point, Calderón criticized the U.S. embargo on Cuba.
"That embargo has been in place since before myself and President Obama were born, and yet it hasn't changed things much in Cuba," Calderón said. "We have to ask ourselves, 'Isn't that enough time to conclude that this strategy has been of little use in changing things in Cuba?' I think it is."
The two leaders also seemed to budge little on a trade spat over cross-border trucking.
Mexico slapped tariffs on $2.4 billion of U.S. goods last month to punish the United States for the cancellation of a pilot program allowing a small number of Mexican trucks to operate on U.S. highways.
The 1994 North American Free Trade Agreement calls for the United States to allow in Mexican trucks, but Washington under pressure from labor unions and environmental groups, has insisted on years of trial programs first.
Obama said he was open to finding a replacement for the trial program, prompting a testy response from Calderón.
"I share the idea that we can advance a lot in labor and environmental issues, but I'm worried that revisiting things that have already proven to work well will simply exacerbate and worsen the situation we have," he said.
Both leaders, however, pledged to work out their differences, noting that Mexico and the United States are still close trade partners and allies in international affairs.
Obama also reiterated that he supports an overhaul of the U.S. immigration system, saying the presence of millions of undocumented workers, many of them Mexicans, drives down U.S. wages.
"My whole goal is to remove the politics of this and take a very practical, common-sense approach that benefits people on both sides of the border," Obama said.
He said he would like to see illegal immigrants "pay a penalty" for breaking the law and then, "if they want to stay in the United States, they have an opportunity over time to earn that opportunity for a legal status."
He gave no timeline for any such proposal.
The arms treaty that Obama pledged to revive is known as the Inter-American Convention Against the Illicit Manufacturing of and Trafficking in Firearms, Ammunition, Explosives and other Related Materials. The pact is more commonly known by its Spanish acronym, CIFTA.
The treaty calls for countries to crack down on the illegal export of weapons, share gun-tracing information and extradite gun-smuggling suspects to other countries.
Groups such as the National Rifle Association have complained that the treaty duplicates existing U.S. laws against weapons trafficking and that gun opponents may eventually use it to try to restrict legal gun ownership in the United States.
Thirty-three nations in the Western Hemisphere have signed the treaty, and 24 have ratified it.
Obama stopped in Mexico City on his way to the fifth Summit of the Americas, a meeting of Western Hemisphere leaders, in the Caribbean nation of Trinidad and Tobago. The leaders will discuss the economic crisis, energy issues and ways to encourage democratic reforms in Cuba.
On Thursday night, Obama had dinner with Mexican lawmakers and Cabinet officials at the National Museum of Anthropology. The museum houses the famous Sun Stone, also known as the Aztec Calendar.
Obama's visit was met mostly by indifference among residents of Mexico City, a metropolis of 20 million people.
About 50 people gathered outside the U.S. Embassy, urging the United States to reform its immigration system and stop raids on undocumented workers. But there were no large demonstrations like the ones that accompanied previous visits to Mexico by President George W. Bush.
Homeland Security Secretary Janet Napolitano was among the U.S. officials who accompanied Obama.