New York - Pope Benedict XVI left Sunday night for Rome after completing a six-day US visit, saying "God bless America" in his final message before boarding his jet, Shepherd One.

The pope was seen off in a ceremony in a terminal building at John F Kennedy International Aiport in New York by US Vice President Dick Cheney, his wife, Lynne, and about 4,000 people including cardinals and other church dignitaries.

Benedict said in response to Cheney's farewell remarks that one of the high points during his US tour was a visit Sunday morning to Ground Zero, which he said will remain "firmly etched in my memory."

He also mentioned the address Friday to the UN General Assembly.

Benedict thanked President George W Bush, New York Mayor Michael Bloomberg and all the high-ranking clergy and government officials who arranged his demanding schedule.

"The time has come for me to bid farewell to your country," the pope said. "The six days that I have spent in the United States have been blessed with many memories and experiences of American hospitality, and I wish to express my deep appreciation for your kind work."

Benedict expressed "profound thanks and appreciation" to all who received him.

Cheney said: "All of America respects this messenger of peace, justice and freedom. From the capital of Washington to this great city of New York, the citizens of our country have received the pope with reverence and affection, with sounds of joy and prayers and thanksgivings."

Cheney said that Benedict would always be welcome in the United States. (dpa)