(CNN) President Trump called for a "major update" to the US immigration system on Thursday, announcing a plan to boost "merit-based" immigration.

Here's a look at what that means, and why it keeps coming up.

'Merit-based' immigration means using individuals' skills to decide whether they should be allowed to immigrate.

Senior adviser Jared Kushner is behind this latest initiative, which emerged after months of talks between Kushner and dozens of conservative groups . One key idea behind it, Trump said in a speech from the White House Rose Garden, would be to attract "the best and brightest all around the world" to come to the United States.

The plan, which faces an uphill battle for consensus even among the Republican Party's own ranks , calls for replacing longstanding family-based immigration rules with a system favoring highly-skilled, financially self-sufficient immigrants who learn English and pass a civics exam.

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