Updated

The three nations of North America are working together to fight off the H1N1 virus that is expected to hit with a vengeance this fall, President Obama said Monday with the leaders of Canada and Mexico by his side.

"In response to the H1N1 pandemic, our three governments have worked closely, collaboratively and responsibly. With science as our guide we resolve to continue taking all necessary preparations and precautions to prepare for the upcoming flu season and protect the health of our people," Obama said at a meeting of the three leaders in Guadalajara, Mexico.

The H1N1 virus appears to have originated in Mexico and the United States has been building its inventory of flu pills as it tests a vaccine. Obama, Mexican President Felipe Calderon and Canadian Prime Minister issued a joint statement saying their nations offered a "joint, responsible and transparent" response to the spreading swine flu threat.

The three men -- attending the annual gathering of the North American Leaders' Summit initiated during George W. Bush's presidency -- also agreed to work together on economic recovery, trade and climate change.

Obama said trade is key to restoring economic growth and calls for a 'buy America' plan are not part of sweeping trend of U.S. protectionism.

Obama offered moral support to Mexico for its fight against drug-related violence. He said drug cartels are the largest violators of human rights in Mexico and has confidence Calderon is cracking down without violating human rights.

However, he did not say whether his State Department would certify that Mexico is protecting human rights in its efforts to fight the drug traders.

U.S. law requires Congress to withhold some drug-fighting funding unless the State Department reports Mexico is respecting human rights. A $100 million installment of a $1.4 billion package is being delayed over rising concerns among some in Congress about the Mexican army's abuses.

Calderon said his government has an "absolute and categorical" commitment to human rights, even those of cartel members.

The Associated Press contributed to this report.