Top Democrats took a jab at Energy Secretary Rick Perry Friday for slowing the flow of federal research dollars to small businesses.

Sens. Maria Cantwell, D-Wash., and Jeanne Shaheen, D-N.H., sent a letter to Perry raising concerns about notices the agency sent to small businesses last month that were awarded grants to not expect the funding. The senators are the top Democrats on the Energy and Natural Resources and Small Business and Entrepreneurship committees, respectively.

"We have consistently heard from small businesses that delays and missed deadlines by federal agencies have an outsize impact on small businesses," the senators wrote to Perry and Small Business Administration chief Linda McMahon. "Unlike large firms and major research institutions, small businesses simply do not have the resources to tide them over when the government fails to meet its own deadlines."

The Energy Department notice, sent in April, said the agency was placing an indefinite delay on funding from the Small Business Innovation Research and Small Business Technology Transfer programs "… until Secretary Perry has an opportunity to be briefed on research projects that will take place under his administration."

The department funds about 10 percent of the total complement of awards under the small business program, which 11 agencies contribute to, according to the letter. The Department of Energy awards more than $217 million of the program's $2 billion in annual funding.

Earlier this week, Cantwell joined with nearly 30 of her Democratic colleagues over concerns that Perry was placing a freeze on advanced research and clean energy program funding. The agency sent out a release late Thursday that announced that it sent grant money to awardees under the Advanced Research Projects Agency for Energy.

The $11 million in funds awarded Thursday to three academic institutions followed a review by Perry to vet how taxpayer money was being spent, the agency said. It suggested that more awards were to follow.

"They are among the first awardees to move forward following the department's review of all taxpayer-funded grants and projects, intended to ensure that each award applied good governance principles consistent with the new administration's policy directives," the agency said.

"The projects moving forward are part of ARPA-E's Next-Generation Energy Technologies for Connected and Autonomous On-Road Vehicles (NEXTCAR) and Renewable Energy to Fuels Through Utilization of Energy-Dense Liquids (REFUEL) programs," it said. "Additional awardees are expected to move forward in the coming weeks."