ANKARA, Turkey (AP) — Turkey's government has accused U.S. prosecutors and judges overseeing a case against a former Turkish economy minister of being an instrument of an alleged conspiracy by U.S.-based cleric Fethullah Gulen against Ankara.

Last week, ex-minister Zafer Caglayan was indicted in a widening U.S. investigation into a Turkish businessman and officials accused of allegedly helping Iran evade sanctions. The move has heightened the tense relations between Ankara and Washington.

Speaking to reporters Monday, Deputy Prime Minister Bekir Bozdag said the accusations against Caglayan were "part of a dirty game" and claimed the U.S. judiciary had become "a tool of the (Gulen movement)."

Turkey blames Gulen's movement for last year's failed coup as well as a corruption scandal that unseated Caglayan and other ministers in 2013. Gulen denies involvement in the coup.