ZURICH (Reuters) - A former UBS UBSG.S banker accused of selling information about wealthy German tax evaders to German authorities was convicted of economic espionage by a Swiss court on Monday.

FILE PHOTO: The logo of Swiss bank UBS is seen in Zurich, Switzerland October 25, 2018. REUTERS/Arnd Wiegmann/File Photo

Rene S., as the 45-year-old ex-banker was called during court proceedings, was sentenced to 40 months in prison and must pay fines and court costs totaling more than 125,000 Swiss francs ($125,300) after being found guilty of charges that included spying and money laundering.

Rene S., who according to court documents has moved to a small town in Germany just across the Rhine River from Switzerland, did not attend the proceedings in Bellinzona this month.

He was acquitted of breaking Swiss banking secrecy laws. It was not immediately clear whether Switzerland would seek his extradition, with Swiss officials in Berne saying such a decision would come only after the appeals process had been exhausted and the judgment finalised.

The case is part of a decade-old dispute between Germany and Switzerland over untaxed assets, a fight they hope will fade now that both countries have joined more than 100 others in agreeing to automatically exchange financial data about their residents’ international accounts.

Switzerland, whose banks have paid out billions to other countries to settle charges they helped foreigners hide wealth, has aggressively prosecuted whistleblowers who leak banking data.

Prosecutors said that between 2005 and 2012, when Rene S. worked for UBS, he illegally collected data about Germans with accounts at the bank and sold the information for 1.15 million euros ($1.31 million) to tax authorities in North Rhine-Westphalia who were seeking to root out tax dodgers.

Rene S.’s lawyer, Moritz Gall, said he expects to appeal. Throughout the trial, Gall has maintained his client’s innocence.

Neither the defendant, who is a Swiss citizen, nor his family could be reached for comment.

Lawyers for UBS, which paid some $300 million in 2014 to settle claims it helped wealthy Germans evade taxes, had contended during the trial that its former employee’s actions had undermined Switzerland as a financial center.

UBS declined to comment after Monday’s verdict.

A decade ago, Germans were believed to be hiding about 150 billion francs in secret accounts in Switzerland and Liechtenstein.

But thousands began declaring their assets after North Rhine-Westphalia, with the federal government’s blessing, started buying covertly collected data.

North Rhine-Westphalia has spent some 17.9 million euros since 2010 on data that helped it recover nearly 7 billion euros ($7.97 billion) in tax revenue.

In turn, Switzerland fought to protect its banking secrecy laws by prosecuting several people, including Rene S., in separate cases where it accused them of illegally handing over documents. [reut.rs/2VDzkHs]

The dispute has included several twists, including the Swiss filing criminal charges in 2012 against three German tax collectors, accusing them of buying account information from informants.

And in 2017, Germany arrested a Swiss man they accused of spying on North Rhine-Westphalia's tax authority, forcing Switzerland's spy agency to defend its practices against friendly neighboring countries. The accused Swiss spy got a suspended prison term. [reut.rs/2FfZgUt]

($1 = 0.8804 euros)

($1 = 0.9976 Swiss francs)