Russian-American ballerina Ksenia Karelina has pleaded guilty to treason charges after she was arrested for donating money to a charity supporting Ukraine.

Russian prosecutors are seeking a 15-year sentence after the security services accused Ms Karelina of collecting money that was used to purchase tactical supplies for the Ukrainian army.

She was detained by authorities in Yekaterinburg, about 1,600km (1,000 miles) east of Moscow after a family visit in February.

The sentence comes one week after Russia and the West carried out the largest prisoner exchange since the Cold War, where 24 people jailed in seven different countries were exchanged.

Ms Karelina's lawyer said the prosecutors' request for a 15-year sentence in a penal colony was too severe as the defendant had cooperated with the investigation.

Mikhail Mushailov also said it was "impossible" for Ms Karelina to have been included in the recent prisoner exchange, because an exchange can only happen once the court verdict comes into force.

"After the verdict, of course, we will work in this direction," Mr Mushailov told reporters on Thursday.

The Los Angeles resident had been living away from Russia for several years and gained American citizenship in 2021.

She travelled to Russia for a family visit back in January, and has since been prevented from returning to her home in Los Angeles.

It has been widely reported that investigators brought the treason charge against her after discovering she had donated around $50 (£39) to Razom, a charity that supports Ukraine.

The charity said it was "appalled" to hear of the amateur ballerina's arrest.