Carnival Corp.'s /zigman2/quotes/202325446/composite CCL -1.25% Carnival Cruise Line said Tuesday it was notifying its guests of cruise cancellations, as the suspension of all operations from U.S. ports has been extended through June 30. The stock rose 3.0% in afternoon trading, and was just below the one-year closing high of $29.79 seen on March 15. ""We know that this is very disappointing to our guests who continue to be eager to sail, and we remain committed to working with the Administration and the CDC to find a workable solution that best serves the interest of public health," said President Christine Duffy. "While we have not made plans to move Carnival Cruise Line ships outside of our U.S. homeports, we may have no choice but to do so in order to resume our operations which have been on 'pause' for over a year." Earlier Tuesday, fellow cruise operator Norwegian Cruise Line Holdings Ltd. /zigman2/quotes/204183397/composite NCLH -0.45% said it still plans to restart cruises out of U.S. ports on July 4, following its request that the Centers for Disease Control and Prevention (CDC) lift the Conditional Sail Order. Carnival's stock has rallied 33.6% year to date, while Norwegian shares have climbed 23.5% and the S&P 500 has tacked on 8.7%.