Trinidad and Tobago
parliamentary democracy

Tunisia
republic

Turkey
republican parliamentary democracy

Turkmenistan
defines itself as a secular democracy and a
presidential republic; in actuality displays authoritarian
presidential rule, with power concentrated within the presidential
administration

Turks and Caicos Islands
NA

Tuvalu
parliamentary democracy and a Commonwealth realm

Uganda
republic

Ukraine
republic

United Arab Emirates
federation with specified powers delegated to
the UAE federal government and other powers reserved to member
emirates

United Kingdom
constitutional monarchy and Commonwealth realm