President Joe Biden on Tuesday signed into law a $430 billion bill that is seen as the biggest climate package in U.S. history, designed to cut domestic greenhouse gas emissions as well as lower prescription drug prices.

At a White House event, Biden was joined by Democratic leaders including Senator Joe Manchin of West Virginia, whose support was crucial to passage of the Inflation Reduction Act along party lines after he had initially opposed a similar measure.

"Joe, we never had a doubt," Biden said of Manchin.

Biden used the event to criticize Republicans as he sought to use a string of Democratic-led legislative victories to help boost Democrats in congressional midterm elections in November.

"In this historic moment, Democrats sided with the American people and every single Republican sided with the special interests," said Biden. "Every single Republican in Congress voted against this bill."

The legislation to fight climate change and lower prescription drug prices aims to cut domestic greenhouse gas emissions. It will also allow Medicare to negotiate lower drug prices for the elderly and ensure that corporations and the wealthy pay the taxes they owe. Democrats say it will help combat inflation by reducing the federal deficit.

Senate Republican leader Mitch McConnell said the new law will have an opposite impact.

"Democrats robbed Americans last year by spending our economy into record inflation. This year, their solution is to do it a second time. The partisan bill President Biden signed into law today means higher taxes, higher energy bills, and aggressive IRS audits," he said, referring to the Internal Revenue Service.