A court on Tuesday sentenced former Olympic snowboarder Kazuhiro Kokubo to three years in prison, suspended for four years, for smuggling cannabis from the United States.

The Tokyo District Court found the 31-year-old conspired with a male acquaintance, already found guilty, to smuggle around 57 grams of a cannabis product in December 2018 from the United States by hiding it using Express Mail Service to Tokyo in a package that arrived at Narita Airport.

"He has been using cannabis regularly for more than 10 years, his deep connection with it is notable and we can't rule out the possibility of him repeating a crime," Judge Chikako Murata said in handing down the ruling.

"It's regrettable you committed the crime despite boasting such achievements in snowboarding," Murata said. "I want you to discipline yourself from now."

Kokubo admitted to the charge during his first trial on Jan. 8, when he confessed he first used cannabis at age 14 and felt apologetic for causing trouble to those around him.

He promised not to use drugs again.

Prosecutors had sought a three-year term, and the defense team a reduced term.

Kokubo competed in men's halfpipe at the 2006 Turin Winter Olympics and 2010 Vancouver Games, finishing 23rd and eighth respectively.