US President Joe Biden Wednesday signed an executive order mandating that the US federal government become carbon neutral by 2050.

The order relies on a variety of clean energy initiatives, including transforming the government's fleet of 600,000 vehicles into electric cars by 2035.

In a statement, the Biden administration said the "whole-of-government effort to tackle the climate crisis" must happen "in a way that creates well-paying jobs, grows industries and makes the country more economically competitive."

"The executive order will reduce emissions across federal operations, invest in American clean energy industries and manufacturing, and create clean, healthy, and resilient communities," the statement said.

What does the executive order say?

Announced by the White House, the executive order mandates federal buildings halve emissions by 2032 and become carbon-free by 2045. The US government owns or leases 300,000 buildings.

The executive order also calls for government buildings to use 100% carbon neutral electricity by 2030.

Overall, the goal is to achieve a 65% reduction in greenhouse gas emissions within a decade.

"As the single largest land owner, energy consumer and employer in the nation, the federal government can catalyze private-sector investment and expand the economy and American industry by transforming how we build, buy and manage electricity, vehicles, buildings and other operations to be clean and sustainable,'' the order said.

The executive order also helps Biden to honor commitments made to world leaders at the UN COP26 conference in Glasgow last month.

What are the reactions from environmental groups?

Environmentalists praised the order as a step in the right direction, although others expressed doubts over the 30-year time span to achieve climate goals when action is needed now.

Lindsey Baxter Griffith, the federal policy director of the Clean Air Task Force advocacy group, told The Associated Press, "We're pleased to see the US federal government, which is the largest electricity purchaser in the nation, focus on fully decarbonizing electricity and investing in solutions that will work across our grid every hour of every day."

However, Bill Snape, a lawyer at the Center for Biological Diversity, disagreed.

"2050 is an extremely weak goal for the federal government to free itself from climate-heating pollution," Snape said.

ar/wmr (AFP,  AP)