WASHINGTON — President Trump directed federal agencies on Wednesday to steer spending toward certain distressed communities across the country — part of his administration’s push to turn a tax break included in last year’s $1.5 trillion tax package into a broader effort to combat poverty and geographic inequality.

Mr. Trump signed an executive order at the White House to push federal resources to so-called opportunity zones — a small but lucrative provision tucked into his signature tax cut that in recent months has vaulted to prominence among real estate developers and other investors.

Mr. Trump told attendees at the meeting that the zones would receive “massive incentives” for private-sector investment. He said the goal of the order was to help “draw investment into neglected and underserved communities of America so that all Americans regardless of ZIP code have access to the American dream.”

The zones are urban, rural and suburban census tracts, designated by governors and approved by the Treasury Department, that either are high in poverty or border high-poverty areas. They are intended to bolster investment in areas that might otherwise lack interest by offering tax breaks to lure funding for start-ups, housing developments and other economic activity. Investors who fund projects in areas deemed opportunity zones can reduce — and in certain cases eliminate — taxes on investment gains.