United States
the U.S. has intensified domestic security measures
and is collaborating closely with its neighbors, Canada and Mexico,
to monitor and control legal and illegal personnel, transport, and
commodities across the international borders; abundant rainfall in
recent years along much of the Mexico-US border region has
ameliorated periodically strained water-sharing arrangements; 1990
Maritime Boundary Agreement in the Bering Sea still awaits Russian
Duma ratification; managed maritime boundary disputes with Canada at
Dixon Entrance, Beaufort Sea, Strait of Juan de Fuca, and around the
disputed Machias Seal Island and North Rock; The Bahamas and US have
not been able to agree on a maritime boundary; US Naval Base at
Guantanamo Bay is leased from Cuba and only mutual agreement or US
abandonment of the area can terminate the lease; Haiti claims
US-administered Navassa Island; US has made no territorial claim in
Antarctica (but has reserved the right to do so) and does not
recognize the claims of any other states; Marshall Islands claims
Wake Island; Tokelau included American Samoa's Swains Island among
the islands listed in its 2006 draft constitution

United States Pacific Island Wildlife Refuges
none

Uruguay
in Jan 2007, ICJ provisionally ruled Uruguay may begin
construction of two paper mills on the Uruguay River, which forms
the border with Argentina, while the court examines further whether
Argentina has the legal right to stop such construction with
potential environmental implications to both countries; uncontested
dispute with Brazil over certain islands in the Quarai/Cuareim and
Invernada streams and the resulting tripoint with Argentina

Uzbekistan
prolonged drought and cotton monoculture in Uzbekistan
and Turkmenistan creates water-sharing difficulties for Amu Darya
river states; field demarcation of the boundaries with Kazakhstan
commenced in 2004; border delimitation of 130 km of border with
Kyrgyzstan is hampered by serious disputes around enclaves and other
areas

Vanuatu
Matthew and Hunter Islands east of New Caledonia claimed by
Vanuatu and France

Venezuela
claims all of the area west of the Essequibo River in
Guyana, preventing any discussion of a maritime boundary; Guyana has
expressed its intention to join Barbados in asserting claims before
the United Nations Convention on the Law of the Sea (UNCLOS) tha