The White House is hosting a virtual summit on the climate crisis today — Earth Day — with 40 leaders representing the world’s major economies, including China. Ahead of the summit, President Biden announced plans to unwind Trump-era rules that prevented California from adopting its own, more stringent auto efficiency standards. He also pledged the U.S. will cut greenhouse gas emissions by at least 50% below 2005 levels by the end of the decade.

Environmental groups criticized Biden’s pledge as inadequate. Food & Water Watch said in a statement, “As the world’s historical largest emitter of climate pollution, we have a duty to do much more, and to act with greater urgency.”

Meanwhile, Mexican President Andrés Manuel López Obrador will propose a migration agreement at this week’s climate summit. The proposal would see Central American asylum seekers and Mexican nationals granted a six-month U.S. work visa and a possible path to citizenship, if they spend three years planting trees and crops across Mexico.