A source of Directors said the move was triggered by the transition of Ethiopia to begin filling the dam before accepting Egypt and Sudan.
Egypt has for some time been against progress on the Nile which could reduce the extent of the water it gets.
Ethiopia says it needs the barrier to provide a reliable power through.
Once fully operational, the dam of the Grand Ethiopian Renaissance (GERD) will be the largest hydropower plant in Africa and provide capacity to 65 million Ethiopians.
"Up to $ 100m or will be affected, including $ 26 million subsidizing which flows to the end of [exercise]," a source from the US Congress reported Reuters news office.
Reporters say the move will likely be seen as US President Donald Trump after Ethiopia rejected nation repel US led intercession with Egypt and Sudan.
The talks slowed on various issues, including requests to Egypt and Sudan that any arrangement should be legitimate authority and how to treat the dam during periods of the dry season.
Gerd is on the Blue Nile upstream from Egypt and can eventually control the progress of the water that the nation gets. The Nile is essential Wellspring Egypt drinking water for both and agribusiness.