MEXICO CITY (Reuters) – Mexican President Andres Manuel Lopez Obrador and U.S. Vice President Kamala Harris spoke by telephone on Wednesday to discuss how to address the causes behind a jump in U.S.-bound migration from Central America.

A sharp increase in apprehensions on the U.S.-Mexico border has posed one of the biggest political challenges to the new administration of U.S. President Joe Biden.

Lopez Obrador has deployed the military and police to stem the flow of people from Central America to the United States, and during the call Harris thanked him for his cooperation on immigration issues, according to a U.S. statement.

“They agreed to continue to work together to address the root causes of migration from the Northern Triangle countries of El Salvador, Guatemala, and Honduras – including poverty, violence, and lack of economic opportunity,” the statement said.

Harris, who Biden last month designated to lead the U.S. response to the immigration challenge, updated Lopez Obrador on American “efforts to surge humanitarian assistance to the Northern Triangle region”, the statement added.

For its part, the Mexican presidency said in a statement the call included discussions to “promote orderly, safe and regular migration”, as well as protections for minors.

“There is a willingness on our part to join forces in the fight against human smuggling and the protection of human rights, especially of girls and boys,” Lopez Obrador said on Twitter after his conversation with Harris.

The two sides also agreed to boost cooperation to target human smuggling and human trafficking.

(Reporting by Raul Cortes and Drazen Jorgic in Mexico City, and Nandita Bose in Washington D.C.; Editing by Dave Graham)