(Reuters) – Direct cash payments can improve financial security, boost consumer spending and may speed up the recovery, according to a letter from a group of economists calling on U.S. policymakers to keep providing direct cash payments to Americans until the economy is stronger.

The stimulus payments should be issued automatically, based on certain economic indicators such as the unemployment rate, until there is enough evidence that the economy is recovering, the group of mostly left-leaning economists said in an open letter organized by the Economic Security Project and The Justice Collaborative.

“The first round of economic impact payments were a lifeline that helped some get by for a few weeks,” the economists wrote. “Even after businesses start to re-open and jobs begin to come back, there will be significant economic fallout, and demand will continue to lag if people don’t have money to spend.”

The letter was signed by 153 economists, including Jason Furman, who chaired the Council of Economic Advisers during the Obama Administration; Claudia Sahm, a former Fed economist; Darrick Hamilton from the Kirwan Institute for the Study of Race and Ethnicity at The Ohio State University; and Indivar Dutta-Gupta, co-executive director at the Georgetown Center on Poverty and Inequality. Some of the signatories are advising the campaign of presumptive Democratic presidential nominee Joe Biden.

The stimulus payments issued in April under the $2.3 trillion CARES Act helped lift spending for lower income households faster than higher income households, with much of the cash going to essentials, according to an analysis by Harvard University’s Opportunity Insights.

The $600 supplement Congress added to weekly unemployment benefits are set to expire at the end of the month, leaving jobless Americans at risk of facing a cash cliff while jobs are still scarce.

Congressional lawmakers are on a two-week recess and will face pressure to make decisions when they reconvene in late July.