The company logo of Noble Group is displayed at its office in Hong Kong, China. REUTERS

Noble Group on Friday said its shareholders approved the company's pending sale of its North American oil business to Vitol U.S. Holdings about $580 million.

Noble said 99.96 percent of the votes cast were in favor of the disposal at a shareholder meeting on Friday.

Earlier this year, Vitol, the world's largest oil trader, closed a deal to buy Singapore-listed Noble's oil liquids unit Noble Americas Corp.

The Hong Kong-based firm, which is in talks with investors to address its deteriorating financial position, has been forced to shrink its business, exiting loss-making and non-core operations in order to survive.

Earlier this month, the company announced the surprise departure of its co-Chief Executive Jeff Frase, just days after it reported a third-quarter loss of $1.17 billion and warned that the operating environment remains challenging.

Noble Group shares ended up 11.6 percent at S$0.24 on the Singapore Exchange. The trader's market capitalization, which once topped $10 billion, has shrunk to $280 million.