Brittney Griner's appeal to President Joe Biden in a handwritten letter continued to garner reaction Tuesday after the WNBA All-Star acknowledged she feared never returning home and asked Biden to not "forget about me and the other American Detainees."

Griner's letter was delivered through her representatives to the White House on Monday, and officials say the president has read it. However Griner's wife, Cherelle, said Tuesday on a morning talk show that she hadn't heard from Biden.

White House press secretary Karine Jean-Pierre was asked repeatedly about Griner on Tuesday during the regular briefing. She said Biden read the letter, but she did not detail his reaction.

"This is very personal to him."

Jean-Pierre did not say whether there were plans for Biden to speak with Griner's family, but did say that National Security Advisor Jake Sullivan and U.S. Secretary of State Antony Blinken both spoke to Griner's wife recently.

Jean-Pierre said Biden wanted to get Griner and other Americans home.

"We are going to use every tool we possibly can to make that happen," Jean-Pierre said.

Griner is in the midst of a trial in Russia that began last week after she was arrested on Feb. 17 on charges of possessing cannabis oil while returning to play for her Russian team. The trial will resume Thursday.

Fewer than 1% of defendants in Russian criminal cases are acquitted, and unlike in U.S. courts, acquittals can be overturned.

Griner's representatives Monday shared a few excerpts from her letter to the president.

"As I sit here in a Russian prison, alone with my thoughts and without the protection of my wife, family, friends, Olympic jersey, or any accomplishments, I'm terrified I might be here forever," Griner wrote.

"On the 4th of July, our family normally honors the service of those who fought for our freedom, including my father who is a Vietnam War Veteran," the Phoenix Mercury center added. "It hurts thinking about how I usually celebrate this day because freedom means something completely different to me this year."

Cherelle Griner was disappointed not to have any direct communication with the White House since the letter was delivered.

"I still have not heard from him and honestly, it's very disheartening," Cherelle Griner said on CBS Mornings.

Cherelle Griner said for Brittney to reach out directly to Biden is an indication of just how afraid her wife is about what's next.

"BG is probably the strongest person that I know. So she doesn't say words like that lightly," Cherelle said. "That means she truly is terrified that she may never see us again. And you know I share those same sentiments. ... I'm sure she was like, 'I'm gonna write him now because ... my family has tried and to no avail. So I'm going do it myself.'"

Griner pleaded with Biden in the letter to use his powers to ensure her return.

"Please do all you can to bring us home. I voted for the first time in 2020 and I voted for you. I believe in you. I still have so much good to do with my freedom that you can help restore," Griner said "I miss my wife! I miss my family! I miss my teammates! It kills me to know they are suffering so much right now. I am grateful for whatever you can do at this moment to get me home."

Griner has been able to have sporadic communications with family, friends and WNBA players through an email account her agent set up. The emails are printed out and delivered in bunches to Griner by her lawyer after they are vetted by Russian officials. Once the lawyers get back to their office, they'll scan any responses from Griner and pass them back to the U.S. to send along.

She was supposed to have a phone call with her wife on their anniversary but it failed because of an "unfortunate mistake," Biden administration officials.

Griner's supporters have encouraged a prisoner swap like the one in April that brought home Marine veteran Trevor Reed in exchange for a Russian pilot convicted of drug trafficking conspiracy. The State Department in May designated her as wrongfully detained, moving her case under the supervision of its special presidential envoy for hostage affairs, effectively the government's chief hostage negotiator.

Griner isn't the only American being wrongfully detained in Russia. Paul Whelan, a former Marine and security director is serving a 16-year sentence on an espionage conviction.