* Defendant who lives in Spain sentenced to eight years
* Charges similar to those in Khodorkovsky's second trial
By Alissa de Carbonnel
MOSCOW, July 18 (Reuters) - A Spanish-based former executive of defunct Russian oil major Yukos was convicted in absentia in Moscow on Monday on multibillion-dollar theft and money laundering charges, news agencies reported.
Moscow's Basmanny district court sentenced Antonio Valdes Garcia, the former director of Yukos trading company Fargoil, to eight years in prison and issued a warrant for his arrest, state-run Itar-Tass and RIA reported.
Valdes Garcia, a dual Russian and Spanish citizen, now lives in Spain which has repeatedly refused Russian extradition requests. He is one of several former colleagues of imprisoned ex-Yukos CEO Mikhail Khodorkovsky to face prosecution in Russia.
The court found Valdes Garcia guilty of stealing $13 billion and laundering $8.5 billion. He was charged with buying oil from Yukos subsidiaries at artificially low prices and reselling it abroad at considerably higher prices, Itar-Tass said.
The case was part of a series of legal proceedings against former Yukos employees widely seen as a Kremlin campaign to tighten state control over oil revenues and punish Khodorkovsky for his perceived challenge to Vladimir Putin, president from 2000-2008 and now prime minister.
Once Russia's richest man, Khodorkovsky was jailed in 2003 and convicted of fraud and tax evasion in 2005.
In a second trial on charges similar to those laid out against Valdes Garcia, he was convicted in December and is serving a 13-year sentence which is due to expire in 2016.
Russia jailed two of Valdes Garcia's alleged accomplices in the pricing scheme -- former Yukos officials Vladimir Malakhovsky and Vladimir Pereverzin -- for 12 and 11 years prison terms respectively in 2007.
Khodorkovsky built a fortune by buying state assets cheaply after the collapse of the Soviet Union in 1991, but his business empire, which once produced more oil than OPEC member Qatar, was split up and sold off after his arrest.
He has repeatedly said that his convictions on theft, fraud and money laundering were ordered by senior officials who wanted to carve up his oil company and that he was prosecuted over business practices that were both legal and used widely.
Russian state-controlled oil firm Rosneft eventually bought the largest production assets, including Yuganskneftegaz, making Rosneft Russia's biggest oil producer.
(Editing by Maria Golovnina)