President Donald Trump during a roundtable discussion on the MS-13 gang in the Cabinet Room of the White House on February 6, 2018 in Washington, DC.

The White House's long-awaited infrastructure plan will reportedly rely heavily on "public-private partnerships" — but it's still unclear whether President Donald Trump himself supports the idea.

NBC News reported Friday that the infrastructure plan, which represents one of Trump's key policy pitches, was originally timed for release near the State of the Union address late last month. The concerns laid out in the article echo much of what CNBC had previously reported regarding Trump's skepticism of public-private partnerships.

During the fall, Trump complained to aides and lawmakers that public-private partnerships were ineffective. His problem with the arrangements, according to officials who have heard his opinion, is based on his experience as a real estate developer, "All you do is end up in court."

One senior administration had told CNBC, "Nothing [from the White House] will mandate public-private partnerships."

In his State of the Union address, Trump said all federal appropriations should be "leveraged by partnering with state and local governments and, where appropriate, tapping into private sector investment."

But Trump himself reportedly requested that D.J. Gribbin, deputy to chief economic advisor Gary Cohn, delay the plan over a reluctance to saddle states and private companies with the burden of a $1.5 trillion spending bill. The plan will use public-private partnerships to fund up to 80 percent of the bill, NBC News said, citing sources who have seen Trump's proposal.

Cohn had worked to convince Trump in January that the federal government's budget couldn't absorb the projected spending increase. The plan is now slated for release on Monday, the same day the White House is also scheduled to unveil its budget proposal.

Read the full report from NBC News.

— CNBC's Kayla Tausche contributed to this article.