Sberbank, Russia's largest lender, is taking the European Union to court in an attempt to loosen Western sanctions imposed over the Ukraine crisis.

The state-controlled bank confirmed it had filed a legal challenge at the General Court of the European Court of Justice on Thursday, but did not comment on the terms of the challenge.

"As the case is subject to a hearing in the Court of the European Union, the bank will not comment on its claim until the final decision is made by the court in accordance with the usual practice for this kind of issue," Sberbank said in a statement.

In July, the European Union imposed sanctions on Sberbank along with four other Russian banks, including VTB Bank, Gazprombank, VEB and Russian Agriculture Bank, in response to Russia’s alleged intervention in Ukraine.

The sanctions imposed on the five banks prohibit European companies from buying or selling new bonds, equity or any other financial instruments with a maturity of more than 90 days issued on their behalf- effectively shutting their access to international capital.