The legislation puts Biden on track to deliver on a major campaign promise important to Latino voters and other immigrant communities after four years of President Donald Trump’s restrictive policies and mass deportations. It provides one of the fastest pathways to citizenship for those living without legal status of any measure in recent years, but it fails to include the traditional trade-off of enhanced border security favored by many Republicans, making passage in a narrowly divided Congress in doubt.

Expected to run hundreds of pages, the bill is set to be introduced after Biden takes the oath of office Wednesday, according to a person familiar with the legislation and granted anonymity to discuss it.

As a candidate, Biden called Trump’s actions on immigration an “unrelenting assault” on American values and said he would “undo the damage” while continuing to maintain border enforcement.

Under the legislation, those living in the U.S. as of Jan. 1, 2021, without legal status would have a five-year path to temporary legal status, or a green card, if they pass background checks, pay taxes and fulfill other basic requirements. From there, it’s a three-year path to naturalization, if they decide to pursue citizenship.