President Donald Trump has taken a variety of actions seen as a "sea change" for immigration policy during his first 100 days in office, and that approach is likely to continue, but experts told Law360 lasting change will depend on congressional action.

Pledging during his campaign to "put American workers first," Trump has made immigration a central focus of his presidency so far. Of the 30 executive orders the White House says Trump will have signed by Saturday's 100-day mark, a significant number have been immigration-related.

Among those are the embattled pair of travel ban orders — one now rescinded and the other suspended by the courts — and a proposed overhaul of the H-1B guest worker program.

He also signed orders aimed at enabling wall construction along the U.S.-Mexico border and requiring more stringent enforcement of immigration laws. Of those enforcement orders, one called for reviving a controversial information-sharing program and another for reducing or eliminating funding for so-called sanctuary cities. That too was blocked, with a federal judge ruling Tuesday that Trump may not withhold federal funding as "a weapon" to be used "against jurisdictions that disagree with his preferred policies."

Another of his controversial immigration stands was an order to prioritize the removal of immigrants who have committed any crimes or abused any kind of public benefit, among other criteria.

Predictably, Trump's actions have proven divisive. Immigration hard-liners at the conservative Federation for American Immigration Reform expressed "cautious optimism" about Trump's first 100 days, with its president issuing a statement Tuesday hailing the "sea change in attitude" at the administration level.

Meanwhile, immigrant advocates like attorney Charles H. Kuck of Kuck Immigration Partners LLC have been highly critical, saying Trump's policies have had the effect of "scaring people who are undocumented."

While Trump has some tools in place to continue down this path, including hand-picked agency appointees and certain executive powers, he's up against a string of court decisions, public opposition and the need for legislative backing — which means anything more lasting will have to come from Congress.