Updated

With U.S.-Mexico relations strained by the killing of a U.S. ICE agent Jaime Zapata  in Mexico and heated rhetoric surrounding the immigration debate, Presidents Barack Obama and Felipe Calderón held a joint press conference on Thursday to emphasize cooperation between the two neighbors on combating drugs and drug violence, and declared a breakthrough in a long-standing dispute over cross-border truck traffic.

Here are the highlights of their joint conference:

Drug War

Obama and Calderón discussed a wide range of issues, including the shooting of the U.S. agent, before speaking to reporters.

During the joint news conference at the White House, Obama praised Calderón for his "extraordinary courage" in fighting the violent drug cartels that have been responsible for deaths on both sides of the border. Obama pledged to speed up U.S. aid to train and equip Mexican forces to help in their efforts.

"Mexico has a full partner with the United States," Obama said. "Our people have a right to be safe in their communities."

Calderón's visit comes three weeks after U.S. Immigration and Customs Enforcement agent Jaime Zapata was shot to death in northern Mexico with a gun smuggled in from the U.S. The incident raised questions in the U.S. about Mexico's ability to control violence and has Obama administration officials considering arming U.S. agents working across the border to ensure their safety.

Calderón offered his condolences to Zapata's family, and said he would work to bring his killers to justice.

"His death must urge us to work together to ensure a prosperous and peaceful future for our region," Calderón said.

Obama and Calderón were also expected to discuss U.S. aid to help support Mexico in the drug war. A senior administration official said the U.S. plans to speed up implementation of the $1.4 billion Merida Initiative, with $900 million to be doled out by the end of the year. The official spoke on the condition of anonymity in order to preview the announcement.

The announcement comes as the State Department issued a report praising Mexico's government for increased drug seizures and better efforts to combat narcotics trafficking and money laundering. But it said Mexican production of marijuana, heroin and methamphetamines was rapidly rising, and that cartels were becoming even more dangerous through use of sniper rifles, grenades and increasingly military tactics.

Lamenting the incident, U.S. Attorney General Eric Holder earlier this week told a congressional panel: "We have to make sure that those kinds of incidents are not repeated and to the extent that that involves the potential arming of them, that's something I think we have to consider."

But during his comments to the press, Calderón made clear that by Mexican law, U.S. agents would be precluded from carrying weapons. Instead, he committed his government to finding alternative ways of protecting U.S. agents.

U.S. and Mexican officials have emphasized that Calderón's visit was planned before Zapata's killing.

Immigration

The contentious debate over immigration dominated Calderón's visit to the White House in May, shortly after Arizona passed a law that makes it a state crime to be in the U.S. illegally and requires police to question people about their immigration status if there's reason to suspect they're illegal. Mexico's government strongly opposes the law, and the Mexican Senate this week urged Calderón to again vehemently make their opposition known to Obama.

Obama also opposes the Arizona law; the White House said that comprehensive immigration reform remains high on Obama's agenda and that the president would update Calderón on the state of the immigration debate in the U.S.

Cross Border Trucking

An Obama administration official had said in advance of the news conference that the two leaders agreed to a phased-in plan that would authorize both Mexican and U.S. long-haul carriers to engage in cross-border operations provided the Mexican trucks meet U.S. safety standards.

Both countries were given this authority under the 1994 North American Free Trade Agreement, but the U.S. has refused to allow Mexican trucks access amid concerns over its ability to meet America's stringent safety and environmental standards.

Mexico has placed higher tariffs on dozens of U.S. products in response to the unresolved dispute. The official said Mexico will agree to lift those tariffs in phases, with all tariffs lifted once the first Mexican carrier receives authorization to travel on U.S. roads.

Negotiating teams are still working out final details of the plan, and are expected to send an agreement to Congress this spring, said the official, who spoke on the condition of anonymity in order to discuss the plan ahead of Obama's public statement.

Based on reporting by the Associated Press.

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