Sending National Guard to the U.S. border of Mexico is "premature and possibly counterproductive," but reviving the assault weapons ban would help end the drug-related violence in Mexico, Sen. John Kerry said Monday.

The chairman of the Senate Foreign Relations Committee said the U.S. and Mexico must work more closely to stop cross-border weapons smuggling and curb the American appetite for illegal drugs that is fueling the violence along the border.

"Americans are worried that the cartels will turn our cities and neighborhoods into the next front in the war. Drug trafficking and the ruthless violence it spawns know no borders. So far, the United States has largely been spared. But it is in our national interest, and it is our solemn obligation, to take steps today to help curtail the killing in Mexico," he said.

But, he added, any response by the U.S. to the violence "must be made in partnership with the Mexicans. The idea of dispatching the National Guard to the border is premature and possibly counterproductive."

Standing near the border in El Paso, Texas, where he convened a field hearing of the Senate Foreign Relations Committee, Kerry said the U.S. needs "to work harder to enforce existing gun laws against exporting weapons across international borders."

The Massachusetts Democrat said the U.S. must "revive the ban on importing assault rifles into the United States," which he attributed to the flood of weapons finding their way to Mexico. The Bureau of Alcohol, Tobacco and Firearms reports that the U.S. is responsible for close to 90 percent of the high-powered weapons that find their way to the Mexican drug cartels.

However, Kerry said that only about one out of every four weapons seized by Mexican authorities last year was submitted to ATF to be traced back to purchasers and sellers in the United States, and he urged the Mexican government to provide ATF with fuller access to these weapons.

Declaring "The drug trade recognizes no borders, and neither should law enforcement," Kerry said the U.S. and Mexico need to form a "combined front" against drug traffickers.

He also called for the Senate to ratify the 1997 Inter-American Convention Against Illicit Trafficking in Weapons and Explosives. Mexico proposed the document -- and the U.S. signed onto it at the time -- under the auspices of the Organization of American States as a means to try to shut down the black market for arms.

"It does not contradict any American gun laws. But ratification would send an important message about our commitment to fight the weapons trafficking that is fueling the violence in Mexico," Kerry said of the 12-year-old treaty.

According to Texas District Attorney Jaime Esparza, crime along the U.S. Southwest border has increased to levels never before seen. Authorities claim 6,290 drug-related deaths in Mexico in 2008.

The U.S. Drug Enforcement Administration says between $18 billion and $39 billion is spent annually in the U.S. on drugs from Colombia and Mexico.

Joseph Arabit, DEA special agent in charge of the El Paso division, said the Justice Department must expand its intelligence capabilities and use information generated by law enforcement agencies and government partners to assist Mexican authorities in attacking the cartels and their allies. He said the department must also focus its efforts on investigation, extradition, prosecution and punishment of key cartel leaders.

The Justice Department must also employ a strategy to specifically target the "leadership and financial assets" of cartels, Arabit said, although he cited the need for more money and more manpower to address the escalating violence.

He added that senior DEA and ATF officials are trying to combating violence associated with the "widespread distribution of drugs on our streets and in our neighborhoods, battles between members of rival cartels on American soil and violence directed against U.S. citizens and government interests."

William McMahon of the ATF proposed more inspection on southbound traffic going from the U.S. into Mexico.

Sen. John Barrasso, R-Wyo., who was present at the hearing, called for an increase in sheriffs along the Southwest border, but he said stricter gun control was not a viable solution.

Despite the increased violence, Arabit said some progress has been made in fighting the drug cartels, including the arrest last month of more than "750 individuals on narcotics-related charges under Operation Xcellerator, a multi-agency, multi-national effort that began in May 2007 and targeted the Mexican drug trafficking organization known as the Sinaloa Cartel."

Kerry added that despite the stress the Mexican government is under in trying to control the violence, it is not a failed state.

"I am troubled by some in some quarters about Mexico becoming a failed state. Mexico is a functioning democracy," he said.

FOX News' Kris Gutierrez and Maggie Kerkman and The Associated Press contributed to this report.