HOUSTON, June 11 (Reuters) - A U.S. judge in Delaware

has approved a calendar extension for a court-organized auction

of shares in the parent of Venezuela-owned refiner Citgo

Petroleum, moving the sales process' final hearing to August 18,

according to a filing on Wednesday.

The new calendar, approved after lawyers representing

Venezuela requested more time for due diligence and to secure

robust bids, sets July 2 as a deadline for making a

recommendation of the auction's winner.