WASHINGTON — The wife of an American held for three years in an Iranian prison appealed to President Trump on Thursday to help secure her husband’s release, invoking Mr. Trump’s recent assistance to another detainee navigating a foreign justice system: ASAP Rocky.

The wife, Hua Qu, said she has seen no progress on the case of her husband, Xiyue Wang, since the United States withdrew from a nuclear deal with Iran in May 2018. “My husband and our family have become innocent victims in an ever-intensifying quarrel between world powers,” Ms. Qu, a Chinese citizen, told reporters in Washington.

She urged the Trump administration to restart diplomatic talks with Tehran — if for no other reason than to help her husband and at least three other American citizens known to be detained in Iran.

Mr. Wang, a naturalized American citizen and Princeton University graduate student who traveled to Iran in 2016 for research, was convicted of espionage — a charge that his family and colleagues deny.