A Swiss court dismissed an appeal by a Kremlin-linked Russian businessman to block his extradition to the United States, rejecting his argument that he was a victim of a U.S. political campaign to snare him on trumped-up insider trading charges.

The Federal Criminal Court said in a ruling released on Monday that it had no reason to question the independence of the U.S. judicial system and that U.S. authorities had presented sufficient grounds for seeking to try Vladislav Klyushin.

Klyushin, whose Russian company offers media monitoring and cyber-security services to clients including the Russian presidency and government, was detained by Swiss police on March 21 on a U.S. arrest warrant.

He was on a family ski trip to Zermatt at the time, his attorney Oliver Ciric had previously said, questioning how U.S. authorities could have been aware of his private travel plans.

Klyushin denies allegations raised in a Massachusetts court that he and accomplices made tens of millions of dollars by hacking into confidential information about listed U.S. companies.

His lawyer attributed the real reason for his arrest and extradition request to his work and contacts within the Russian government that gave him access to security information. He said an appeal had been lodged with Switzerland's supreme court.

In June, the Swiss Federal Office of Justice (FOJ) approved Klyushin's extradition to the United States. It rejected a Russian request in April to extradite Klyushin to face trial there. The FOJ ruled the crime he was accused of was not punishable in Switzerland, a key test in extradition decisions.

The United States in April imposed a broad range of sanctions on Russia to punish it for interfering in last year's U.S. election, cyber hacking, bullying Ukraine, and other alleged malign actions.