A Russian court on Tuesday rejected American basketball star Brittney Griner's appeal of her nine-year sentence on drug charges, the state-run RIA Novosti news agency reported,raising the stakes of United States efforts to negotiate her release.The 32-year-old was handed nine years in prison in August after security officers at a Moscow airport found vape cartridges with a small quantity of cannabis oil in her luggage in February."I really hope that the court will adjust this sentence because it has been very, very stressful and very traumatic," Griner told the Moscow regional court in the city of Krasnogorsk, appearing via video link.Judge Yelena Vorontsova announced that the star athlete's sentence would remain unchanged, RIA Novosti reported.In a statement published on the White House website, United States President Joe Biden's National Security Advisor Jake Sullivan slammed the court's ruling as a "sham judicial procedure.""The president has demonstrated that he is willing to go to extraordinary lengths and make tough decisions to bring Americans home, as his administration has done successfully from countries around the world," the statement reads.Ahead of the hearing, Griner's lawyers Maria Blagovolina and Alexander Boykov said in a statement that"Brittney does not expect any miracles to happen but hopes that the appeal court will hear the arguments of the defense and reduce the term."Her legal team has the ability to appeal the verdict again in a higher court following Tuesday's decision.When she was arrested, the two-time Olympic basketball gold medallist and Women's NBA champion had been in Russia to play for the professional Yekaterinburg team, during her off-season from the Phoenix Mercury.She pleaded guilty to the charges but said she did not intend to smuggle drugs into Russia, while her defense lawyers presented doctors notes authorizing her to use medical marijuana, which is illegal in Russia.Griners case came amid fierce tensions between Moscow and Washington over Russia's military offensive in Ukraine.In August, Moscow said it was ready to discuss a prisoner swap for Griner, but there hasbeen no apparent progress.Media reports have suggested that Griner and another American jailed in Russia, Paul Whelan a former United States Marine arrested in December 2018 and accused of spying could be traded for Viktor Bout, a Russian arms trafficker serving 25 years in jail on a 2012 conviction.AFP contributed reporting.