KRASNOGORSK: A Russian court on Tuesday dismissed U.S. WNBA basketball star Brittney Griner's appeal against a nine-year sentence for possessing and smuggling vape cartridges containing cannabis oil, paving the way for her to be sent to a penal colony, in a court case that Washington has called "sham."

U.S. President Joe Biden, whose administration in late July had proposed a deal for a prisoner swap with Russia to secure the release of Griner and former U.S. marine Paul Whelan, said he will not let up efforts to bring them home.

"We're in constant contact with Russian authorities to get Brittney and others out. So far we've not been meeting with much positive response but we're not stopping," he said.

Griner, a two-time Olympic gold medallist, was arrested on Feb. 17 at a Moscow airport, a week before Russia sent troops into Ukraine. The souring of ties between Russia and the West has further complicated the talks between Washington and Moscow to secure her release.

Griner and her lawyers had asked for acquittal or at least a reduction in her sentence, which they said was disproportionate to the offence and at odds with Russian judicial practice.

After retiring for no more than 30 minutes to consider the appeal, the presiding judge said the original verdict was upheld "without changes" except for the counting of time served in pre-trial detention as part of the sentence.

The state prosecutor had said Griner's Aug. 4 sentence of nine years in a penal colony was "fair", but Alexander Boykov, one of her lawyers, had told the three-judge panel sitting in Krasnogorsk, on the outskirts of Moscow:

"No judge, hand on heart, will honestly say that Griner's nine-year sentence is in line with Russian criminal law," Boykov said.

Griner's lawyers in a statement said it would be some time before Griner was moved to a prison colony, and that they had not yet decided whether to try to launch another appeal. They also added her case file would have to be translated into English, which would also take some time.

It was not immediately clear where she would be sent.

"The severity and cruelty of the sentence applied to Griner shocks people around the world," Boykov said.

Biden's national security advisor Jake Sullivan, in an earlier statement, described Griner's conditions as "intolerable circumstances" and the trial she had to go through "another sham judicial proceeding."

Permitted to make a final statement by live video link from her detention centre in the town of Novoye Grishino, just outside Moscow, Griner said how stressful her eight-month detention and two trials had been.

"I was barely over the significant amount [of cannabis oil] ... People with more severe crimes have gotten less than what I was given," she said.

'I DID NOT INTEND TO DO THIS'

Griner apologised for what she said was an honest mistake, as she had at her original trial, saying: "I did not intend to do this", and asking the court to take into account the fact that she had pleaded guilty.

She has said she used medical cannabis to relieve the pain from a series of sports injuries. Both recreational and medicinal uses are prohibited in Russia.

Wearing a black and red lumberjack shirt over a black hooded top, the 32-year-old alternately sat or stood in her cell, sometimes with head lowered, sometimes leaning against the white bars.

When asked if she had understood the verdict, she merely replied "Yes" before being led away.

U.S. State Department spokesperson Ned Price said in a briefing Washington has been telling Moscow, including in their talks in recent days, to engage on the U.S. proposal.

"At the very least they should engage seriously and constructively and in good faith. If that happens, we are prepared to see to it and to take steps tomorrow," Price said.

U.S. Charge d'Affaires Elizabeth Rood, the ranking U.S. diplomat in Moscow, told media waiting outside the court that she had not been allowed to speak to Griner before or after the hearing.

Griner's lawyers said her biggest fear was not being exchanged and having to serve her entire sentence in Russia. "She had hopes for today as each month, each day away from her family and friends matters to her."