(The Hill) – Former NBA star Dennis Rodman reportedly said he is traveling to Russia to help secure the release of WNBA player Brittney Griner, who was recently sentenced to nine years in a Russian prison for possessing cannabis oil cartridges.

Rodman, who previously inserted himself into US-North Korea diplomacy, told NBC News on Saturday he secured permission to travel to Russia and is “trying to go this week.”

The U.S. State Department has a do not travel advisory in effect for Russia, which also warns Americans in the country to leave immediately.

The Hill has reached out to the State Department for comment on Rodman’s plans.

The Biden administration is currently negotiating the release of Griner and former U.S. Marine Paul Whelan, having reportedly proposed an exchange involving Russian arms dealer Viktor Bout.

Rodman, a hall-of-famer who played for several NBA teams, including time with the Chicago Bulls alongside Michael Jordan, has visited Russia before and once called Russian President Vladimir Putin a “cool guy.”

In 2014, Rodman took credit for the release of Kenneth Bae from North Korea, a nation he visited multiple times despite high tensions with the U.S. Rodman once called North Korean leader Kim Jong Un a “friend.”

FILE – In this Jan. 8, 2014, file photo, Dennis Rodman sings Happy Birthday to North Korean leader Kim Jong Un, seated above in the stands, before an exhibition basketball game at an indoor stadium in Pyongyang, North Korea. (AP Photo/Kim Kwang Hyon, File)

The former NBA player told NBC News on Saturday that he “knows Putin well” and was confident he could negotiate with the Russian leader.

Griner was arrested by Russia in February as tensions between the Russian government and the U.S. spiked over the pending invasion of Ukraine. The US has officially declared Griner as being wrongfully detained.

The WNBA star pled guilty to carrying the cannabis oil cartridges, but argued she packed them into her suitcase by mistake and had no criminal intent.

Griner has appealed the nine-year sentence a judge handed down this month.