The United States plans to join with other NATO nations in increasing ground and naval forces in Eastern Europe as part of the military alliance's response to Russia's incursion in Ukraine, the White House said Wednesday. President Barack Obama's deputy national security adviser, Ben Rhodes, said NATO was aiming to provide "a continuous presence to reassure our allies." While he would not detail specific countries where the additional resources would be sent, he noted that the U.S. was particularly focused on efforts to bolster Poland, Estonia, Lithuania and Latvia.