The $2 trillion bipartisan pandemic relief deal reached early Wednesday morning will massively expand unemployment insurance, effectively turning it into four months of salary replacement for many workers sidelined by the coronavirus.

The provision will add a flat $600 a week to unemployment benefits, Senate Minority Leader Chuck Schumer said Wednesday, and flow to a broader range of unemployed workers.

"We call it unemployment compensation on steroids," the New York Democrat said on the Senate floor. "Every American worker who is laid off will have their salary remunerated by the federal government so they can pay their bills."

By extending the benefit to workers who are furloughed rather than just those who are laid off, the provision will allow workers to stay connected to their jobs, Schumer said, meaning that the business can quickly reemploy them when the virus-related shutdowns end.

Expanding unemployment benefits was one of the key demands of congressional Democrats in negotiating the massive relief package.

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A Democratic aide familiar with the negotiations said that the Democrats' unemployment proposal was included within the economic relief package to give employers the most flexibility to make decisions in their best interest while still ensuring their employees or former employees are financially stable. Democrats argue that the GOP's plan to provide grants to small businesses to keep their employees on the payroll, also included in the deal, would not cover many employees, such as those who have already been laid off, gig workers, and those who are self-employed.

The $600 a week, effectively a $15 hourly wage for people working 40 hours, would be in addition to whatever each state is giving their workers as base unemployment benefits.

"The $600 flat benefit every week makes the unemployment insurance more progressive," said Kyle Pomerleau, an economist at the American Enterprise Institute. "The additional cash will be helpful for those who have very low incomes who have lost their job."

Pomerleau said that the current unemployment insurance, without Schumer's proposal, would be insufficient for low-income workers who would only get close to the minimum wage from unemployment insurance at the moment. Most state's unemployment insurance is calculated based on a percentage of a former employee's salary, meaning higher earners receive more financial aid and lower earners receive less.