Port & Free Zone World (P&FZ), the direct owner of global ports operator DP World  is considering refinancing options for an $850 million financing facility, the prospectus for DP World's London listing showed.

Shares in DP World, the third largest ports operator in the world and one of the more profitable units of debt-laden Dubai World, will begin trading on the London Stock Exchange on June 1, the company said on Wednesday.

State-owned conglomerate Dubai World is the parent company of P&FZ, which owns 80.5 per cent of DP World and has two representatives on the latter's board of directors, the prospectus, published May 25, said.

"The company understands that Port & Free Zone World is considering to refinance its outstanding net debt facilities of approximately $850m, secured in part against certain of its shares in the Company, in short to medium term," DP World said in the prospectus.

"Options to refinance the facilities include, inter alia, further bank loans, asset disposals, public market bond issues (including equity-linked bonds) or the sale of shares in the Company."

The company was not immediately available for comment when contacted by Reuters.

 Dubai has been restructuring state-linked firms to deal with a debt pile estimated at $115 billion built up during a boom that put the emirate on the map for extravagant construction projects.

The emirate faces about $30 billion in refinancing to 2012.

Last year, Dubai World reached a debt deal with creditors on a $26 billion restructuring which foresees asset sales and repayment after five and eight years.-Reuters