President Biden’s suspension of border wall construction does not violate congressional spending rules, the Government Accountability Office said Tuesday, a decision that rejects Republican claims the administration is legally obligated to resume building the barrier.

Biden ordered a halt to his predecessor’s signature project in January, and last month his administration said it would return $2 billion in border wall funds to the Defense Department. The administration also said it would use an additional $1.9 billion in congressionally appropriated Department of Homeland Security money to prioritize environmental restoration and site cleanup, rather than adding more steel and concrete.

The GAO, the nonpartisan oversight arm of Congress, said the Biden administration’s moves amounted to a “programmatic delay,” rather than an impoundment of funds that would violate appropriation laws.

“DHS and the Office of Management and Budget (OMB) have shown that the use of funds is delayed in order to perform environmental reviews and consult with various stakeholders, as required by law, and determine project funding needs in light of changes that warrant using funds differently than initially planned,” the GAO found.

The agency drew a distinction between Biden’s pause and President Donald Trump’s suspension of security aid to Ukraine in 2019, a move at the center of his impeachment trial last year.

The Biden administration hasn’t canceled border construction contracts or said it is ending the project outright. By meeting environmental review requirements and other procedural safeguards — which can lead to long delays — the Biden administration is technically following the law, the GAO found. That wasn’t what occurred with the Ukraine funding.

“OMB did not justify the withholding of Ukraine security assistance funding by presenting evidence of any statutory prerequisites that needed to be satisfied before funds could be obligated,” the GAO said. “Here, delays in the obligation and expenditure of DHS’s border barrier appropriations stem from the time required to meet applicable statutory requirements and develop plans for the use of the funds that consider current circumstances.”

Abdullah Hasan, a spokesman for the OMB, said in a statement that Biden’s border wall proclamation in January “directed Federal agencies to comply with appropriations law at every step.”

Trump completed more than 450 miles of new steel barriers along the Mexico border at a cost of more than $11 billion. His administration planned to build nearly 300 additional miles, and the halt to construction left unfinished gaps in the barrier, as well as segments that have been blasted and bulldozed through mountains and cut a swath through the desert.