Mexican President Andres Manuel Lopez Obrador on Thursday used a climate change summit to tell US President Joe Biden that force will never solve the issue of mass migration.

Lopez Obrador said people moving north to the United States in search of better lives at a time of climate change are "exceptional" and that new policies are needed to address the growing movement.

"The migration phenomenon, as we all are aware of, is not going to be solved by force," he said.

Tensions between the United States and its southern neighbor have been simmering for years over illegal border crossings, many of them involving citizens of poorer Central American countries.

The issue was at the center of Donald Trump's surprise rise to power in 2016, when he stoked often virulent anti-immigrant rhetoric. Biden has vowed to change the US approach but is struggling to make good on his promise of a more humane attitude while also dealing with a sharp increase in asylum seekers and migrants searching for work.

Lopez Obrador put the issue in the context of upheaval linked to climate change.

Migrants "are the people that help in the development of different nations," he said.

"We have to order these migration flows and organize them in a very human way, with the love of nature and the responsibility to give to the future generations a planet where they will be able to live."

sms/dw