(ANSA) - BELGRADE, JUN 28 - US officials told CNN that White House officials are losing faith in the fact that Ukraine will ever be able to regain all of the territory it has lost to Russia during the previous four months of war, even with the more advanced weaponry the US and its partners intend to provide. President Joe Biden's advisors have also begun arguing whether or not Ukrainian President Volodymyr Zelensky should modify his definition of "winning" to account for the potential that his country has irreparably diminished, CNN stated. US sources underscored to CNN that this more negative view does not imply that the United States intends to exert pressure on Ukraine to make formal territory concessions to Russia in order to stop the war. (ANSA).