The president will meet Monday with Attorney General Loretta E. Lynch to finalize a series of new gun control measures and will announce his package of proposals soon after, according to several individuals who spoke on the condition of anonymity because the plan is not yet public.

One of the main proposals Obama is poised to adopt would require some unlicensed gun dealers to get licenses and conduct background checks on potential buyers. The change is aimed at occasional dealers, including some who sell online frequently or rent tables at gun shows but do not have a storefront.

Obama began examining how he could tighten the nation's gun rules after October's mass shooting at Umpqua Community College in Roseburg, Ore. Administration lawyers have spent months reviewing various proposals to make sure they can withstand legal challenges.