On Tuesday, the Moscow City Court announced the decision against moving Gershkovich to another prison, permitting him house arrest or granting him bail.
Secretary of State Antony Blinken "made a determination that Evan Gershkovich is wrongfully detained by Russia," said State Department spokesman Vedant Patel.
Gershkovich was detained by Russian authorities last week, who accused him of spying, signalling a significant ratcheting of both Moscow's tensions with the United States and its campaign against foreign news media.
"Evan's lawyers were able to meet with him in prison today. They said Evan's health is good, and he is grateful for the outpouring of support from around the world. We stand with Evan and continue to call for his immediate release," the statement said, according to CNN.
"In light of the established evidence of the US national's illegal activities, his future will be determined by the court. The American embassy in Moscow was duly notified about his detention," the ministry said.
The US-based daily newspaper, The Wall Street Journal (WSJ), has once again called for the release of its reporter Evan Gershkovich, who was arrested in Russia over espionage charges.
In a statement, FSB said, "Gershkovich acting on the instructions of the American side, collected information constituting a state secret about the activities of one of the enterprises of the Russian military-industrial complex," read a WSJ report.