Swiss bank documents wanted by a UK probe into the late Uzbek ruler Islam Karimov's eldest daughter can be transferred to Britain, Switzerland's Federal Criminal Court decided in a ruling released Wednesday.

The court dismissed a challenge by a company which opposed transferring the papers relating to accounts with banks in Geneva and Zurich, claiming they would not be of any use to the money laundering probe launched by Britain's Serious Fraud Office relating to Gulnara Karimova.

She is currently in jail in Uzbekistan on embezzlement and criminal conspiracy charges.

As "first daughter", Karimova was among Uzbekistan's powerful elite, serving in diplomatic posts, including in Geneva, and tipped as a potential successor to Karimov.

She organised a fashion week, had her own jewellery line, released pop singles and ran entertainment TV channels.

But several years before her father's death in 2016, she suddenly fell from favour and feuded publicly with her mother and sister before being placed under house arrest.

UK investigators are on the trail of £40 million ($48.8 million) used to buy property in Britain, which they believe may have been laundered.

"Between 2004 and 2012, corrupt sums were allegedly paid by three telecommunications companies to obtain an illegal competitive advantage in the Uzbek telecommunications market," the federal court ruling said.

The document detailed elements of the British investigation, which alleged that funds were channelled in around 30 instalments via companies based in Gibraltar, Hong Kong and the British Virgin Islands, and their accounts held in Switzerland, Cyprus and Latvia.

"The use of numerous companies... spread across several countries, bank accounts in several countries and the size of the sums... constitute sufficient indications allowing the suspicion of, prima facie, money laundering acts," the Swiss court said, thereby justifying assisting the British investigation.

Karimov ran a regime in the central Asian state largely inspired by Soviet authoritarianism before his death in 2016.

His daughter was sentenced in March 2020 in the former Soviet republic to serve just over 13 years in prison.

She has faced allegations of involvement in corruption in many countries.

However, in Switzerland, the Federal Criminal Court found that in a case where she is alleged to have received bribes, prosecutors had interpreted the status of public official too broadly when applying it to Karimova.