Mexico City, Dec 22 : Mexico aims to address the causes of immigration with the incoming administration of US President-elect Joe Biden, Mexican President Andres Manuel Lopez Obrador said. Lopez Obrador's remarks on Monday came after he held a 20-minute telephone conversation with Biden over the weekend, in which they agreed to strengthen bilateral immigration policy, reports Xinhua news agency. According to the Biden-Harris team, during the call the "President-elect thanked Lopez Obrador for his congratulations and expressed his commitment to build a strong relationship with Mexico on a foundation of respect for the rule of law and advancing shared values". "The President-elect emphasized the need to reinvigorate US-Mexico cooperation to ensure safe and orderly migration, contain Covid-19, revitalise the economies of North America, and secure our common border," the team said in a statement. Addressing a briefing here on Monday, the Mexican Ppresident said: "He (Biden) knows that people leave their places of origin out of necessity, not for pleasure, so what you have to do is to get to the causes and promote the development of the south." At the height of the migrant caravans headed toward the US border in 2019, Lopez Obrador's administration established a Comprehensive Development Plan for Central America and southern Mexico. At the time, US President Donald Trump even threatened Mexico with punitive trade tariffs if it did not curb northward migration. According to government estimates, 38 million Mexicans live in the US. /IANS