sentences:  In July 2017 Vučić visited the United States and met with U.S. Vice President Mike Pence, where they discussed U.S. support for Serbia's efforts to join the European Union, the need for continued reforms, and further progress in normalizing the relationship with Kosovo.Referencing the proposed land swap arrangement between Serbia and Kosovo, U.S. national security advisor John Bolton has said that the United States would not oppose a territorial exchange between Kosovo and Serbia to resolve their long-running dispute.The U.S. State Department continues to maintain that the full normalization of relations between Serbia and Kosovo is "essential for regional stability", which Vučić has said before.