The Obama administration said Tuesday that the US Congress needs to sign off on long-delayed reforms to the International Monetary Fund to ensure it can get adequate aid to Ukraine. US Treasury Secretary Jacob Lew said the administration is working with Congress to put together a $1-billion loan guarantee facility for Ukraine, where a new government is struggling with depleted coffers and institutions in need of reform. But he said the IMF must be at the center of any international assistance package, and that approval of the IMF's 2010 reforms by Congress would enhance the ability to help Ukraine. "We re working with Congress to approve the 2010 IMF quotalegislation, which would support the IMF's capacity to lend additional resources to Ukraine, while also helping to preserve continued US leadership within this important institution," Lew said in a statement. The United States is by far the largest stakeholder in the IMF, but Congress' long resistance to approving reform has essentially blocked it. The Obama administration has repeatedly tried to get Congress to agree to a reshaping of the crisis lender -- most recently in a budget bill in January, but it failed. The Treasury suggests they will tie the two together -- IMF reforms and aid for Kiev -- in one effort. "At a time when the US is at the forefront of international calls in urging the Fund to play a central and active first responder role in Ukraine, it is imperative that we secure passage of IMF legislation now so we can show support for the IMF in this critical moment," a senior Treasury official said. In addition, "the 2010 reforms will unlock additional financing commitments to the IMF from other countries, providing a larger and more stable source of financing for the IMF."