Insolvent oil refiner Petroplus
said on Wednesday it planned to negotiate a sale of its assets and would delist its stock and a $150 million convertible bond from the Swiss bourse by mid-May.

The Swiss-based company, heaving under high debt and poor refining margins, said it had applied for permission from a local Swiss court to dispose of its assets to pay out to creditors.

Petroplus intends to apply to delist its shares from the SIX Swiss exchange after five and a half years on the bourse and expects the last trading day to be on May 11, 2012.

The oil refiner also plans to delist its $150 million 4 percent convertible bond due in 2015.

Petroplus's future was thrown into doubt late last December, when lenders froze the credit lines it relied on to buy oil for its refineries. Despite last-ditch talks with creditors, the company was forced to apply for insolvency in late January.

Administrators are now independently looking for buyers for Petroplus' five refineries.

Because of this the company said it does not have an overview of its business activities and has applied to be exempt from financial reporting.

(Reporting by Caroline Copley; Editing by Hans-Juergen Peters)