Former Vice President Al Gore has filed a lawsuit against the Middle Eastern media group Al Jazeera, accusing it of fraud and breach of contract in its $500 million purchase of Mr. Gore’s Current TV cable channel.

The dispute centers on Al Jazeera’s refusal to turn over “tens of millions of dollars” remaining in an escrow account and still owed to the selling shareholders of Current TV, according to a statement from David Boies, the lawyer representing Mr. Gore and a Current TV co-owner, Joel Hyatt, who are suing on behalf of all the selling shareholders.

“Al Jazeera America wants to give itself a discount on the purchase price that was agreed to nearly two years ago,” Mr. Boies said. “We are asking the court to order Al Jazeera America to stop wrongfully withholding the escrow funds that belong to Current’s former shareholders.”

Mr. Gore and Mr. Hyatt filed the case in the Delaware Court of Chancery in Wilmington. Few other details are known, as the complaint has been sealed by the court, but Mr. Gore and the other selling shareholders have petitioned to make the case public.