Wall Street Journal (WSJ) reporter Evan Gershkovich, who was taken into custody last week in Russia on espionage charges widely seen as politically motivated, has appealed against his detention.
Russian media reported that lawyers for the 31-year-old journalist filed the appeal with the Lefortovo district court on April 3.
AFP quoted a court spokeswoman as saying that a date for the appeal hearing will be announced this week.
Gershkovich was denied access to his own lawyer on March 30 when the same court agreed to a request from Russia's Federal Security Service (FSB), the main successor of the Soviet-era KGB security agency, to hold Gershkovich under arrest for two months.
The court spokeswoman told AFP that the court assigned lawyer who represented Gershkovich at the arraignment filed the appeal.
Gershkovich, a U.S. citizen based in Moscow, had been in Yekaterinburg reporting about the attitude of Russians toward the Kremlin's war against Ukraine and on the Wagner mercenary group.
Moscow has accused Gershkovich of collecting information about one of the enterprises of the Russian military-industrial complex, which constitutes a state secret. The charge carries a penalty of up to 20 years in prison.
The White House and the WSJ have denied the allegations and said Gershkovich, who was detained in Yekaterinburg, is an accredited journalist.
NATO chief Jens Stoltenberg on April 3 condemned the arrest and demanded the "immediate release" of Gershkovich.
"His arrest is of great concern. It is important to respect freedom of the press, the rights of journalists and the right to ask questions and to do their job," he said at a news conference in Brussels ahead of an April 4 meeting of foreign ministers from the alliance, where the matter is expected to be discussed.
U.S. Secretary of State Antony Blinken urged Russian counterpart Sergei Lavrov on April 2 to release Gershkovich during a rare phone call.
"We are keenly and strongly and closely tracking this issue and working as diligently as we can to secure his release," a spokesman said.
The U.S. State Department has yet to classify the arrest of Gershkovich as a wrongful detention, White House National Security Council spokesman John Kirby told journalists on April 3, adding that the department was working on that.
"We have been pushing hard since the moment we found out he was detained by the Russian on ridiculous charges," he added.
Some analysts have speculated Gershkovich's arrest is a move by Russia to set up a prisoner swap similar to one that took place in December.
That exchange involved U.S. women’s basketball star Brittney Griner, who was held in Russia for 10 months after being arrested at a Moscow-area airport on drug charges. She was released and returned to the United States for Russian arms dealer Viktor Bout.
Many analysts said the trade favored the Kremlin, since Bout was a convicted global arms dealer while Griner was held on minor charges, and that the White House should have forced the inclusion of Whelan -- a former U.S. Marine being held in Russia since 2018 on what Washington calls trumped-up charges.
Griner on April 2 urged the White House to use "every tool possible" to win the release of Gershkovich.