Wall Street Journal reporter Evan Gershkovich appears in an undated handout image taken in an unknown location (Reuters)

US President Joe Biden said on Friday that Russia should let Evan Gershkovich go in his first public reaction to the detention of The Wall Street Journal reporter on espionage charges, according to a White House pool report.

"Let him go," Biden said when asked about his message to Russia regarding Gershkovich's case.

On Wednesday, Gershkovich was detained in the Russian city of Yekaterinburg on suspicion of espionage in favor of the United States. The Russian Federal Security Service said the journalist had been collecting classified information about the activities of one of Russia's military-industrial complex firms.

On Thursday, the Lefortovo District Court of Moscow ruled that the reporter be put in pre-trial detention for two months.

The Wall Street Journal said it would seek Gershkovich's immediate release.

"The Wall Street Journal vehemently denies the allegations from the FSB and seeks the immediate release of our trusted and dedicated reporter, Evan Gershkovic. We stand in solidarity with Evan and his family," the newspaper said in a statement.

The reporter's lawyer, Daniil Berman, told sources that he was not permitted to enter the courtroom, noting that other lawyers may have been assigned to defend Gershkovich in his stead.

No plans to expel Russian diplomats over Gershkovich detention: Biden

In the same context, Biden said he has no plans at the moment to expel Russian diplomats in response to the detention of Gershkovich in Russia.

Following the arrest of Gershkovich over espionage suspicions on Thursday, The Wall Street Journal has called on the US authorities to consider retaliatory measures such as the expulsion of the Russian ambassador and all Russian journalists working in the country.

"That’s not the plan right now," the US President told reporters when asked if he is going to expel Russian diplomats.

Russia to provide consular access to Gershkovich

On its part, Russian Foreign Ministry Spokesperson Maria Zakharova affirmed on Friday that Moscow will provide consular access to the Wall Street Journal reporter in accordance with internal procedures.

"In accordance with our internal procedures, this [consular] access will, of course, be provided," Zakharova told the Rossiya 1 broadcaster.

The Russian diplomat considered that the United States exposed itself by reacting to the arrest of Gershkovich in such a way, warning that things will escalate if threats against Russian journalists continue.

"They [the Americans] immediately move on to, indeed, threats, reprisals against Russian journalists. If this logic continues in the public space, the situation will escalate," Zakharova said.

The Spokesperson noted that there is no investigation on the part of the United States to understand what happened to the journalist.

Kremlin Spokesperson Dmitry Peskov assured that all journalists who have valid accreditation in Russia can continue their journalistic activities in the country without facing any restrictions.

On Thursday, Zakharova wrote on her Telegram channel that Gershkovich was not engaged in any journalistic work.

"What an employee of the US paper The Wall Street Journal was doing in Yekaterinburg has nothing to do with journalism," Zakharova said.

"Unfortunately, this is not the first time that the status of a 'foreign correspondent', a journalistic visa, and accreditation are used by foreigners in our country to cover up activities that are not related to journalism," she noted.

According to the Russian Spokesperson, Gershkovich "is not the first well-known Westerner who got caught in action."

Peskov also later said that Gershkovich was caught red-handed.

"The only thing I can say is that, as far as we know, he was caught red-handed," Peskov told reporters when asked if Moscow will cooperate with the US intelligence services on the matter.