CAIRO (Reuters) - The operator of a giant cargo ship that blocked the Suez Canal in March said on Thursday that while a final agreement with authorities was being concluded, it would take more time for the vessel to be released and able to sail.

       The Japanese owners and insurers of the ship were locked in a compensation dispute with the Suez Canal Authority, but announced on Wednesday that an agreement in principle had been reached.

       "It may take some further time for the agreement to be concluded, for the vessel to be released from arrest and prepared for onward transit," ship operator Evergreen Line said in a statement.

       The Ever Given container ship has been anchored in a lake between two stretches of the canal since it was dislodged on March 29. It had been grounded across the canal for six days, blocking hundreds of ships and disrupting global trade.

       (Reporting by Jonathan Saul; editing by Emelia Sithole-Matarise)