The federal government’s disaster relief agency said on Friday that it had “significant concerns” about how a tiny Montana company won a contract for up to $300 million to rebuild part of Puerto Rico’s hurricane-ravaged electrical grid.

The Federal Emergency Management Agency, which normally would help pay for storm recovery, warned that it might refuse to cover any costs if the contract between Whitefish Energy and the Puerto Rico Electric Power Authority, known as Prepa, was found to be improper.

“Based on initial review and information from Prepa, FEMA has significant concerns with how Prepa procured this contract and has not confirmed whether the contract prices are reasonable,” the federal agency said in a statement on Friday.

In a copy of a contract circulating online, whose authenticity has not been verified, the power authority “represents and warrants that FEMA” approved the deal. But in its statement, FEMA said, “Any language in any contract between PREPA and Whitefish that states FEMA approved that contract is inaccurate.”