WASHINGTON — President Trump on Thursday will unveil a plan to overhaul parts of the nation’s immigration system that would impose new security measures at the border and significantly increase the educational and skills requirements for people allowed to migrate to the United States.

The proposal, senior administration officials said on Wednesday, would vastly scale back the system of family-based immigration that for decades has allowed immigrants to bring their spouses and children to live with them, the officials said. In its place, the new plan would provide opportunities for immigrants who have specific skills or job offers to work in the United States, provided they can demonstrate English proficiency and educational attainment, and pass a civics exam.

Jared Kushner, the president’s son-in-law and a White House adviser, spent months working on the plan, which will serve as a central part of Mr. Trump’s re-election campaign message. Working with him was Stephen Miller, the president’s top immigration adviser, but the plan falls short of the more extreme measures that Mr. Miller has long pressed the president to adopt and that have long been opposed by Democrats in Congress.

[Update: Trump’s immigration plan gets a Rose Garden rollout and a cool reception.]

Attempts by Mr. Trump’s two predecessors, George W. Bush and Barack Obama, to overcome those kinds of differences and achieve a bipartisan consensus on immigration policy ended in failure. Since then, the divisions between the parties have only worsened, and there is little chance the new proposal will change that. For different reasons, the broad outlines of the plan described on Wednesday are certain to be unpopular with lawmakers on both sides of the aisle.