US President Joe Biden has signed a $700bn (£579bn) bill that aims to fight climate change and healthcare costs while raising taxes mainly on the rich.
The act includes measures to make good on decades of congressional promises to curb the price of prescription drugs.
The final version is more modest in scope than the $3.5tn package first envisaged by Democrats.
A flagship of Biden’s agenda, the bill could provide a boost ahead of the mid-term elections.
Voters casting their ballots in November will decide whether Biden’s Democrats retain control of Congress for two more years.
The president hailed the bill as he signed it on Tuesday as the “final piece” of his domestic agenda.
The package invests $375bn to fight climate change – the most significant federal investment in history on the issue.
An analysis by scientists with the Climate Action Tracker says the bill will reduce future global warming by “not a lot, but not insignificantly either”.
It is projected to lower US emissions by up to 44% by 2030, compared with the current US trajectory, which would lower emissions by up to 35%, according to an analysis by the Rhodium Group, a consultancy.
The bill does not require companies to reduce their emissions but includes tax incentives for firms to invest in renewable energy and rebates for people who buy electric cars or invest in energy-efficient home improvements.
In a major breakthrough, the package also allows the government to negotiate lower prices for some prescription medicines provided under its Medicare health insurance program for those aged over 65.
Agencies