The Biden administration is making plans to announce one of the largest immigration relief programs in recent history, developing a policy that would offer legal status to hundreds of thousands of immigrants living in the country without proper documents, four people familiar with the plans told CBS News.

A program being developed by White House officials would offer work permits and deportation protections to unauthorized immigrants married to U.S. citizens, as long as they have lived in the U.S. for at least 10 years, the sources said, requesting anonymity to talk about internal government plans.

The proposal, known as "Parole in Place," would also open up a pathway to permanent legal status and U.S. citizenship for some beneficiaries by removing an obstacle in U.S. law that prevents those who entered the U.S. illegally from obtaining green cards without leaving the country.

Another plan being prepared by the Biden administration would streamline the process for so-called DREAMers and other undocumented immigrants to request waivers that would make it easier for them to obtain temporary visas, such as H-1B visas for high-skilled workers, the sources said.