WASHINGTON, Feb 6 (Reuters) - President Donald Trump has placed holds on tens of billions of dollars in congressionally-approved spending for projects across the U.S. that range from Iowa soybean farmers adopting greener practices to a Virginia railway expansion, a Reuters analysis found.

Project managers and advocates warn continued delays could take a toll on local economies. Democratic lawmakers say the halts are the building blocks to “impoundment,” presidential refusal to release money authorized and appropriated by Congress, which they say is illegal.